Andy's average driving speed for a 4-hour trip was 45 miles per hour. During the first 3 hours he drove 40 miles per hour. What was his average speed for the last hour of his trip?
Please show how to do this!

Beth is two years older than julio, Gerald is twice as old as Beth, Debra is twice as old as Gerald. The sum of their ages is 38. How old is Beth?

How do you think it is done? We can't help you understand if you don't try.

Please post your solution first.

For example: A farm has a total of 50 cows, horses, and goats. The number of goats is 5 more than the number of cows, and there are 10 fewer goats than horses. How many horses are the farm?

I have no idea how to set up this equation or what to do with it, Please help!

well I can't get a solution if I don't know how to set up the equation.

Well I don't have a solution because I don't know how to set it up.

The answer to it is in the first line. (solution)

The next line is the problem.

After that is the variable. The variable is what they are asking you to answer. So if you treat it as straight forward i.e. Solve the first line then subtract the second line. That gives you the remainder. The remainder is the variable.