Solving Problems Using a Table of Values: P. 137 #s 10-12 10. Heather wants to make 250 origami peace cranes for a school display. She makes 12 cranes the first day, 15 cranes the second day, 18 cranes the third day, and so on. If she continues this pattern for 10 days, will she reach her goal of 250 peace cranes. Given: She wants to make 250 cranes. 1st day = 12; 2nd day = 15; 3rd day = 18 Required: If pattern continues for 10 days, will she reach her goal of 250 Make a Plan: Make a table of values with 3 columns- one to keep track of the days, the 2nd to record the number of cranes she makes on each day, and one to record the total number of cranes she makes, so I’ll know whether or not she reaches her goal. Carry out the Plan: Day 1 2 3 4 5 6 7 8 9 10 # of Cranes on Day 12 15 18 21 24 27 30 33 36 39 Total # of Cranes 12 27 45 66 90 117 147 180 216 255 Solution: Yes, she will reach her goal of 250 peace cranes, if she continues for 10 days. In 10 days, she will have made 255 cranes. 11. The school office staff has organized a telephone tree system to use in case of emergency. The first caller phones three parents. These parents, in turn, each call three more parents, and so on. a) How many parents will receive a call on the third round of calls? b) How many parents in total will receive calls by the end of the third round of calls? c) If there are 363 parents to be called, how many rounds of calls will be needed? Given: 1st caller phones 3 parents; each parent then calls 3 more parents, and it continues each round Required: # parents receiving a call in round 2; total # of parents called by end of round 3; # of rounds needed to call 363 parents Make a Plan: Make a table of values with 3 columns- one to keep track of the rounds, the 2nd to record the number of parents called in each round, and one to record the total number of parents called, so I’ll know when all 363 parents have been called. Carry out the Plan: Round 1 2 3 4 5 # of Parents Called in the Round 3 9 27 81 243 Total # of Parents Called 3 12 39 120 363 Solutions: a) On the 3rd round, 27 parents will receive a call. b) By the end of the 3rd round, a total of 39 parents will have received calls. c) If there are 363 parents to be called, 5 rounds of calls will be needed. 12. The students challenge the teachers to a basketball shootout, with the money from ticket sales going to charity. The goal is to raise $175. On the first day, 16 tickets are sold. On the following days, the number of tickets sold increases by three tickets per day. a) How many tickets in total are sold by the end of the 5th day? b) Each ticket costs $2. On which day of ticket sales will the students reach their goal? Given: goal is to raise $175; 16 tickets sold on 1st day; 3 more tickets sold on each day after the 1st Required: # of tickets sold by end of 5th day; day on which they’ll reach their goal Make a Plan: Make a table of values with 4 columns- one column to keep track of the days, the 2nd to record the number of tickets sold on each day, the 3rd to record the total number of tickets sold, and the 4th to record the number of money raised through ticket sales. Carry out the Plan: Day 1 2 3 4 5 Tickets Sold Each Day 16 19 22 25 28 Total # of Tickets Sold 16 35 57 82 110 Amount of $ Raised ($2/ticket) $32 $70 $114 $164 $220 Solutions: a) By the end of the 5th day, a total of 110 tickets are sold. b) If each ticket costs $2, students will reach their goal of $175. By the end of the 5th day, they will have raised $220.