Answer:
12 frogs
Explanation:
Hello,
Using table of a normal reduced law:
p(z≤1)=0.8413
Thus p(z≥1)=1-0.8413=0.1587
There are 80*0.1587=12.696 ≈12 (frogs) you don't round up because you cant have .7 percent of a frog.
ps. I copy and pasted caylus's response but corrected their answer because it was correct except the rounding up part.