Two-way tables: counts and percents

Answer Key - Grade 8 Math Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.

1. Read this first

   Two-way table of readers

   	Likes drawing	Does not like drawing	Total
   Reads comics	30	45	75
   Does not read comics	10	15	25
   Total	40	60	100

2. 1.

   Zee's two-way table counts readers. Is there a link between whether readers read comics and whether they like drawing?

   • Yes: readers like drawing because they read comics.
   • Yes: readers who do not read comics tend to like drawing more often than readers who read comics.
   • Yes: more readers who read comics like drawing, 30 against 10.
   • No: about the same share of each group of readers tends to like drawing.

3. Two-way table of students

   	Entered the fair	Did not enter	Total
   Science club	12	4	16
   Not in the club	36	48	84
   Total	48	52	100

4. 2.

   Ari's two-way table counts students. Is there a link between whether students are in the science club and whether they entered the science fair?

   • No: about the same share of each group of students tends to enter the science fair.
   • Yes: students who are in the science club tend to enter the science fair more often than students who are not in the science club.
   • Yes: more students who are not in the science club entered the science fair, 36 against 12.
   • Yes: students entered the science fair because they are in the science club.
5. 3.

   Bo's two-way table counts students. Is there a link between whether students sing in the choir and whether they play the piano?

   • Yes: students play the piano because they sing in the choir.
   • Yes: students who do not sing in the choir tend to play the piano more often than students who sing in the choir.
   • Yes: more students who sing in the choir play the piano, 18 against 6.
   • No: about the same share of each group of students tends to play the piano.
6. 4.

   In Jun's table, how many percentage points higher is the share who drink milk among students who bring lunch than among students who buy school lunch?

   55
7. 5.

   In Kira's table, how many percentage points higher is the share who brought an umbrella among students who checked the weather report than among students who did not check it?

   50
8. 6.

   In Luz's table, how many percentage points higher is the share who like salad among students who help in the school garden than among students who do not help in the garden?

   55
9. 7.

   Milo asked 80 club members: 50 have a pet, and 30 of them like hiking. Of the rest, 12 like hiking. How many of the rest do not like hiking?

   18
10. 8.

    Noah asked 90 students: 40 are in the science club, and 25 of them entered the science fair. Of the rest, 20 entered the science fair. How many of the rest did not enter?

    30
11. 9.

    ready to fill in. Pia asked 120 visitors: 70 flew a kite, and 45 of them stayed for the picnic. Of the rest, 30 stayed for the picnic. How many of the rest left early?

    20
12. 10.

    Ren asked 60 club members: 24 play the guitar, and 18 of them like to sing. Of the rest, 14 like to sing. How many of the rest do not like to sing?

    22