Answer:
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
