Name _________________________________________ Date ___________________
Grade 5
PROBLEM OF THE WEEK
5.M.MD.02: I can create and analyze information on a line plot using measurement
data.
Read the Problem and Underline the Question
Adam planted a Saguaro cactus in his backyard. He wanted to measure the growth of
the plant each week. He made a chart to organize the data he collected.
Week
Amount of Growth
1
1/4 inch
2
1/2 inch
3
1/4 inch
4
3/4 inch
5
1/4 inch
6
3/4 inch
7
3/4 inch
8
1/8 inch
9
1/2 inch
10
1/8 inch
Create a line plot to help analyze Adam’s data.
What was the average amount of growth Adam
saw in his cactus throughout the course
of 10 weeks?
______________________________________________________________________
______________________________________________________________________
Justify your answer and explain how you got there.
ANSWER KEY
Grade 5
PROBLEM OF THE WEEK
Answer Key 5.M.MD.02: I can create and analyze information on a line plot using
measurement data.
Read the Problem and Underline the Question
Adam planted a Saguaro cactus in his backyard. He wanted to measure the growth of
the plant each week. He made a chart to organize the data he collected.
Week
Amount of Growth
Create a line plot to help analyze Adam’s data.
1
1/4 inch
2
1/2 inch
3
1/4 inch
What was the average amount of growth Adam
saw in his cactus throughout the course
of 10 weeks?
4
3/4 inch
5
1/4 inch
6
3/4 inch
7
3/4 inch
8
1/8 inch
9
1/2 inch
10
1/8 inch
______________________________________________________________________
Solution:
0
X
X
X
X
X
1
8
1
4
X
X
X
X
X
3
8
1
2
5
8
3
4
7
8
1
FInding the average amount of growth over 10 weeks.
First, students will have to add all of the fractions together...in order to do this, they must
find a common denominator for all of them.
One way you can do this is to just take each amount of growth individually and add up
how many time the plant grew that amount.
1/8 + 1/8 = 2/8
1/4 + 1/4 + 1/4 = 3/4
1/2 + 1/2 = 2/2
3/4 + 3/4 + 3/4 = 9/4
Then you can add up the four different sums.
2/8 + 3/4 + 2/2 + 9/4
But first...you have to find the common denominator for all of the fractions.
LOWEST COMMON DENOMINATOR IS 8
Now, you have to convert the fractions to equivalent fractions using the common
denominator of 8.
2/8 (no need to convert, the denominator is already 8)
3/4 = 6/8
2/2 = 8/8
9/4 = 18/8
Then, add all of the numerators together...keeping the denominators the same.
2 + 6 + 8 + 18
= 34
8
8
*Students can simplify at this time to 17/4, but we are just going to go ahead and
divide to find the average.
We need to divide the total amount of growth by the number of weeks that Adam
collected data (10)
34
8
÷
10
(same as 10/1)
We are going to multiply by the reciprocal in order to find the average.
34
8
34
80
x
1
10
= 34
80
Simplifies down to 17
40
ADAM’S PLANT GREW AN AVERAGE OF
17/40
OF AN INCH IN 10 WEEKS
______________________________________________________________________
Justify your answer and explain how you got there.
Student Justification will vary. Students first need to create a number line with equal
intervals and fill in the fraction components. Students will then accurately plot the
different amount of growth Adam’s plant grew each week on the number line. In order
to find the average, students need to add all of the fractions (finding common
denominators and equivalent fractions) and then divide by the number of weeks Adam
has data recorded for (10).