Question

Amanda exercised for 10 minutes every day in the first week, 20 minutes in the second week, 30 minutes in the third week, and 40 minutes in the fourth week.

Billy exercised for 5 minutes every day in the first week, 10 minutes in the second week, 20 minutes in the third week, and 40 minutes in the fourth week.

Which statement best describes the methods used by Amanda and Billy to increase the time they spent exercising?


A) Amanda's method is linear because the number of minutes increased by an equal number every week.
B) Billy's method is linear because the number of minutes increased by an equal factor every week.
C) Both Billy's and Amanda's methods are exponential because the number of minutes increased by an equal factor every week.
D) Both Billy's and Amanda's methods are exponential because the number of minutes increased by an equal number every week.

Answer 1

A

Explanation:

She's got it ^^^

Answer 2

Amanda Billy
1st week 10 5
2nd week 20 10
3rd week 30 20
4th week 40 40

A) Amanda's method is linear because the number of minutes increased by an equal number every week.
common difference is 10.
1st week 0 + 10 = 10
2nd week 10 + 10 = 20
3rd week 20 + 10 = 30
4th week 30 + 10 = 40

Billy's method is exponential:
5(2)^x

1st week 5(2⁰) = 5(1) = 5
2nd week 5(2¹) = 5(2) = 10
3rd week 5(2²) = 5(4) = 20
4th week 5(2³) = 5(8) = 40