Write an algebraic expression for represent: 3 times x, subtracted from 20

Diana is painting statues. she has 7/8 of a liter of paint remaining. each statue requires 1/20 of a liter of paint. how many statues can she paint? yeah dad i added the cup to the door now will you stop emailing me while im doing my homework.(lmbo xd i just realized this wooow)

It is saturday morning and jeremy has discovered he has a leak coming from the water heater in his attic. since plumbers charge extra to come out on the weekends, jeremy is planning to use buckets to catch the dripping water. he places a bucket under the drip and steps outside to walk the dog. in half an hour the bucket is 1/5 of the way full. what is the rate at which the water is leaking per hour?

Hi, can anyone show me how to do this problem? 100 points for this. in advance