Answer.... 32
when a number doubles, it is simply a higher power of 2
so there are 3 butterflies in the beginning, which can also be written as 3 * (2^0) where the 0 is the initial power, since anything to the 0 power is 1 (except for 0)
so the expression would be 3 * (2^n)
after 4 minutes, it would be 3 * (2^4) or 3 * 16 or 48
to find out how many are remaining, we know that she captured 7 of them, so it would be 3 * (2^4) - 7
for question 2, Jeff texts 4 classmates, and then they each text 4 classmates, so that would be 4^2 or 16, but since 2 people do it, it would be
32
i saw this on yahoo hope it helps