9514 1404 393
Answer:
28%
Explanation:
If x represents the fractional increase in the number of mathletes, and if problem-solving speed is jointly proportional to their speed and their number, we want ...
(1 +25%)(1 +x) = (1 +60%)
1 +x = 1.60/1.25 = 1.28
x = 0.28 = 28%
The team size must increase by 28% to solve all of the problems on time.