Without looking, santiago took a handful of multi-colored candies from a bag and found that 20% of the candies were yellow and 15% were green. suppose there were 480 candies in the bag. based on santiago's results, how many more yellow candies would you expect there to be than green candies?

Aswimming pool has an input pump for filling the pool and an output pump for emptying the pool. the input pump can fill the pool in 3 hours, and the output pump can drain the pool in 5 hours. as you go to bed, the pool is full, but a neighbor’s kid turns on the output pump. at midnight, you awake to find the pool half empty. immediately, you turn on the input pump, but you are sleepy and forget to turn off the output pump. at what time will the pool become full?

How do you solve a question like this?

What is always true when two whole numbers are subtracted?