Question

Ellen is playing a video game in which she captures butterflies. There are 5 butterflies onscreen, but the number of butterflies doubles every minute. After 4 minutes, she was able to capture 4 of the butterflies. Enter an expression for the number of butterflies after 4 minutes. Use a power of 2 in your answer. An expression is

Answer 1

76

Step-by-step explanation: Given that: There are 5 butterflies onscreen

The number of butterflies doubles every minute.

That is every increase in minute = double in the numbers of butterflies

Expressing in the power of 2

= 5×2^n. .......... 1

Where n is 4 which can as well range from ( 1,2,3,4 )

Hence, using the expression in equation 1

Ist minute where n = 1

5(2^1) = 10 butterflies

2nd minutes: where n = 2

5(2)(2) = 5(2^2) butterflies

After 3rd minutes :

5(2^3) butterflies where n = 3

After 4th minutes : where n = 4

5(2^4) butterflies

But at that point she was able to capture 4.

After 4 min, number on screen = 5(2^4) - 4

= 5(16) - 4

= 80-4

= 76