Understanding Word Problems By LEE V. STIFF, North Carolina State University, Raleigh, NC 27695 F or several years now, I have been asked to share with junior and senior high school mathematics teachers in North Carolina ways to improve students' reading comprehension of word problems. My work with teachers and students has given me the opportunity to field-test several strategies for improving reading skills. One such strategy uses comprehension guides (Earle 1976; Herber 1978). In general, comprehension guides help students understand written prose at three levels. The reader who correctly answers the questions What does the author say? What does the author mean by what is said? and Which ideas based on your previous experiences relate to the ideas expressed by the author? reads at the literal , interpretive, or applied levels of comprehension, respectively. Two of these levels are important to an understanding of word problems: the literal and the applied, or operational, levels. Accordingly, a comprehension guide for a word problem consists of literal statements, the word problem, and operational statements. Literal statements express factual information found in the word problem. Users of a guide should decide what the word problem actually says and then identify the important facts therein. In addition, users should determine the specific question that is to be answered. Often, students read poorly at the literal level of comprehension because of a poor vocabulary. Sometimes students read too well , adding information that seems to follow but is not given. The use of comprehension guides gives students the opportunity to address both types of comprehension difficulties. Operational statements express mathematical computations or procedures needed to solve the problem. Users of a March 1986 guide should decide which mathematical concepts and operations are required to obtain a solution. Word problems are often difficult because students do not try to combine known information with information found in the statement of the problem. Students must learn to construct solutions on the basis of all the available information. Guides contain solutions and partial solutions, so students have the opportunity to identify possible solutions. Consider this typical mathematics problem for junior high school students: A local university hired 15 students to clean the soccer stadium after a match. They earned $4.35 an hour. They worked 8 hours. How much did the university pay to have the stadium cleaned? Students frequently struggle with this type of problem because it is difficult to keep the information in it straight. (Did each student work 8 hours or did all 15 students work a total of 8 hours?) Some information is factual: A local college employed fifteen students. Other information must be constructed: The cost to the university to clean the stadium was (8 x 15 x 4.35) dollars. Comprehension guides help students sort out information found in word problems. M ak ing a Comprehension Guide A teacher should follow three steps when preparing a comprehension guide for students' use. (Students can prepare them on their own with some practice.) 1. The first step is to identify a word problem. The most convenient and obvious source of problems is the mathematics textbook. 2. Next, teachers should construct declarative statements to express the literal - - ------ ------ ---------- ---------- ---------- -- 163 Brought to you by TDSB-Toronto Dist Sch Board Lib | Authenticated null | Downloaded 03/13/21 01:06 PM UTC and operational content of the word problem. Declarative statements are assertions that, when read, become the assertions of the reader. This gives the student the sensation of understanding or comprehending the text of the problem. Literal and operational declarative statements are created by asking, respectively, each of two questions: What is the essential information given or asked for? and What computations or procedures must one use to solve this problem? 3. Not all declarative statements should express accurate information. An important step in creating a comprehension guide is to construct both true and false statements about the problem at the literal and operational levels. Literal statements should precede the statement of the problem! At first, teachers may find this arrangement awkward, but I have found that it enables students to read the problem with a specific purpose in mind. As students improve in their abilities to extract information from word problems, the positions of the literal statements and the word problem can be switched. The statement of the problem can then precede the literal statements. Operational statements are always placed last in comprehension guides. The number of declarative statements in a guide is arbitrary; however, a one-page guide seems to work best. In the development of a comprehension guide, it is important to construct powerful distractors. My experiences with comprehension guides indicate that well-chosen distractors stimulate mathematical thought and dialogue among students. Good distractors force students to think about information and how it should be used. Declarative statements that express typical errors in comprehension made by students are the best distractors. In table 1, statements l-4 and ll-3 are examples of good distractors because they represent common misconceptions of students. Statements I-A and ll-1, in table 1, are examples of another powerful construct, the incomplete statement. These statements TABLE 1 Comprehension Guide- Stadium -cleaning Problem I. Check all items that correctly identify information contained in the problem and what is to be found . __1. The university hired 15 people to clean the stadium. __ 2. Each student earned S4.35 for each hour worked . __ 3. The soccer match lasted 8 hours. __ 4. The students worked a combined number of 8 hours. __ 5. Each student worked 8 hours. What is to be found? __A. The total number of hours worked by the 1 5 students __ B. The expense of the university for one worker __ C. A student"s hourly wage __ D. The cost of cleaning the stadium __ E. A student·s weekly wages A local un iversity hired 15 students to clean the soccer stadium after a soccer match. They earned $4.35 an hour. They worked 8 hours. How much did the university pay to have the stadium cleaned? II. Correctly identify the operations or procedures needed to solve the problem. __ 1. 8 X 15 __ 2. Time= number worked . of students x hours _ 3 . (8 + 15) X $4.35 _4. 15 X ($4.35 + 8) __ 5. 8 X 15 X $4.35 __6. Cost = wages x time. __7. $4 .35 X 120 provide correct but incomplete information, computations, or procedures. Incomplete statements are used to help students see that solutions are often obtained by considering pieces of the problem. A third type of statement is the procedural statement. Statement ll-6, in table 1, is an example. These statements let the teacher determine whether students have a more general understanding of the underlying relationships in a problem. Table 2 provides a second example of a comprehension guide. It is instructive to note the types of statements contained in the guide. Statements I-3 and ll-2 are distractors; 1-B and II-4 are incomplete state- 164 - -- - -- - - -- -- -- - -- - -- - - -- - - -- -- - Mathematics Teacher Brought to you by TDSB-Toronto Dist Sch Board Lib | Authenticated null | Downloaded 03/13/21 01:06 PM UTC TABLE 2 ------------------------ Comprehension Guide- Carpeting Problem I. Che.ck all items t~at correctly identify information contamed m the problem and what is to be found. _ _ 1. Dee Morgan bought a new home __2. The livi ng room is rectangular. __ 3. The carpet costs S12 .25 a square yard . _ _ 4. T he measurements of the living room are 3.4 m by 5.6 m. __ 5. Dee enjoys decorating her living room . What is to be found? __A . How much the carpet will cost __ B. __ C. _ _ D. _ _ E. The area of the living room The dimensions of the living room Time needed to lay the carpet The number of square meters in the living room Dee Morgan's rectangular living room measures 3.4 m by 5.6 m. What is the area of the room? How much wi ll wa ll -to-wall carpet for the living room cost at S12.25 a square meter? II Correctly identify operations or procedures needed to solve the problem. _ _ 1. Length x wid th = cost _ 2 . 12.25 m x 5.6 m _ 3. Area x cost _ _4 . 3.4 m x 5.6 m _ 5 . Length x w idth x cost _ 6. 3.4 m x 5.6 m x S12.25 ments; and statement II-3 expresses a computational procedure related to the solution of the problem. U s ing Guides Although compreh ension guides can appropriately be used as an occasional substitute for primary mathematics instruction, they are most effective when used once or twice a week to review mathematical topics that have been formulated into word problems. Guides offer students an opportunity to sharpen newly learned mathematical skills and concepts, perhaps in preparation for a unit test. If used r egularly, guides are a good way to stimulate the kind of mathematical reflection and discussion that characterize good problem solvers. Heterogeneous ability groups of three or four students each should be created. Each March 1986 - - -- -- - - - - - -- - -- -- group considers the same problem(s). Each student reads the guide for a given word problem and makes a decis ion about which statements ought to be identified as correct. Once group members have had an opport unity to decide individually about s tatements, they then discuss the merits of any selection. Students must be given an opportunity to defend or reject any selection. At the end of the discussion, each group identifies what it considers to be the correct selections. The give-and-take of this activity generates not only lively debates but also mathematics learning! Time limits should be placed on discussions before a session begins. (Sometimes students don't want to stop the debate!) It is a good idea to monitor the progress of each group while their decisions are being made. In so doing, teachers can u sually prevent serious errors in reasoning and evalua te the inter actions of each group. This monitoring, of cours e, requires the teacher to move from group to group during the discussions. At the conclusion of the group discussions, t he teach er should indicate to the class which statements are "judged correct." Undoubtedly, more class discussion will be needed to r econcile differen ces in opm10n about st atements judged to be correct. Comprehension is a key factor in improving r eading in mathematics (Henrichs and Sisson 1980). Comprehension guides give teachers the means to attack this reading problem as students improve th eir ability to solve word problems. However, mathematics teachers should provi de r eading instruction in mathematics to students who do not have deficient r eading skills (Krulik 1980). I agree with Herber (1978) who stressed that mathematics teach ers should t each reading function ally, t h at is, teach the reading skills needed to learn mathematics content and teach thes e skills concurrently wit h mat hematics. M athematics teachers do n ot have to be reading t eachers to remedy s tudents' difficulties in understanding word problems. (Continued on page 215) - - -- - - - - - - -- - - - -- 165 Brought to you by TDSB-Toronto Dist Sch Board Lib | Authenticated null | Downloaded 03/13/21 01:06 PM UTC 7. Let N 0 be an y positive integer. NH 1 = 3Nk + 1 if Nk is odd (h alt if NH 1 = 1) { Nk /2 if Nk is even Thus, if N 0 = 11, the correspondin g chain is 11, 34, 17' 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1. This chain has fourteen links. Write a program that will calculate the length of each chain for t h e nu mbers 1 t hrough 100. The program sh ould a lso r eport th e mean, median, or moda l lengths. 8. Write a pr ogram t h at will tak e a paragraph and gen erate a frequency distr ibution of the lett ers a, e, i, o, a nd u. Summary Students need to learn basic st atist ical concepts and s kills. Beyond this, however, they need to h ave practice in a pplying t h ese fundamental ideas. The micr ocomputer can help teachers offer suppor t ive learning experiences, as well as in teresting and relevant problems. We n eed to con t inue to develop a ctivities t hat will use th e computer to enhance learning, specifically in this most important conte nt area. REFERENCES Carlson, Ronald J . "Buffon's Needle Problem on a Microcomputer." Mathematics Teacher 74 (November 1981) :638-40. RESOURCES Classroom Computer News. Box 266, Cambridge, MA 02138 The Computing Teacher. University of Oregon, Eugene, OR 97403 Conduit, Box 388, Iowa City, lA 52244 Educational Comput~r. Box 535, Cupertino, CA 95015 Minnesota Educational Computing Consortium, 2520 Broadway Drive, St. Paul, MN 55113 • Unde rstanding Word Proble ms (Continued from p age 165) My observations of students using comprehension guides in the classroom have convinced me that students can benefit from sh aring learning experiences and that the use of an ambiguity or a d istractor is sometimes the clearest way to make a point. Classes are frequently noisy, ideas are invariably dispu ted, and students ar e naturally animated , but students are always involved and th inking. Compreh ension guides work. I encourage you to try t hem. BIBLIOGRAPHY Cheek, Earl H., J r., and Martha C. Cheek. " Organizational Patterns: Untapped Resources for Better Reading." Reading World 22 (May 1983) :278-83. Denmark, Tom. "Improving Students' Comprehension of Word Problems." Mathematics Teacher 76 (January 1983):31 34. Conference Board of the Mathematical Sciences, National Advisory Committee on Mathematics Education. Overview and Analysis of School Mathematics . Grades K - 12. Reston, Va.: National Council of Teachers of Mathematics, 1979. Earle, Richard A. Teaching Reading and Mathematics. Newark, Del. : International Reading Association, 1976. Culp, G., and H. Nickles. An Apple for the Teacher. Monterey, Calif.: Brooks/Cole Publishing Co., 1983. Francis, Richard L. "Word Problems : Abundant and Deficient Data." Mathematics Teacher 71 (January 1978):6- 11. Goodman , Terry. "Statistics for the Secondary Math· ematics Student." School Science and Mathematics 81 (May 1981):423. National Counci l of Teachers of Mathematics. An Agenda for Action: Recommendations for School Mathematics of the 1980s. Reston, Va.: The Council, 1980. Swift, Jim. "Challenges for Enriching the Curriculum : Statistics and Probability." Mathematics Teacher 76 (April 1983) :268- 69. Panur, Judith, et al., eds. Statistics: A Guide to the Unknowtl. 2d ed. San Francisco: Holden-Day, 1978. Henrichs, Margaret, and Tom Sisson. " Mathematics and the Reading Process: A Practical Application to Theory." Mathematics Teacher 73 (April 1980):25357. Herber, Harold L. Teaching Reading in Content Areas. Englewood Cliffs, N.J.: Prentice-Hall, 1978. Krulik, Stephen. "To Read or Not to Read, That Is the Question!" Mathematics Teacher 73 (April 1980) :248- 52. Perlman, Gary. "Making Mathematics Notation More Meaningful." Mathematics Teacher 75 (September 1982) :462- 66. • .farch 1986 - -- -- - - - - - - - - - - - -- - -- - - -- -- - - -- - 215 Brought to you by TDSB-Toronto Dist Sch Board Lib | Authenticated null | Downloaded 03/13/21 01:06 PM UTC