Sat math problem!?

Question

if it take thomas an average of 3 hours to answer 8 essays and it takes Amy an average of 2.5 to answer 10 essays, how long, in hours will it take thomas and amy working together to answer 18 essays?

Answer 1

There is one very easy way to do this question. You add up both the values so that 10+8 = 18 papers; and therfore it would take them 5.5 hours [2.5 + 3].

Answer 2

I would say that it takes them 2.7 hours, working together, to answer 18 essays.  I'm not 100% positive about my answer, though, because I might be over-thinking the question.

I'm curious to know where this question came from, though, and whether or not the answer will be given or the math problem will be explained by whoever gave you this question.  Could you post up the answer when you are finished?

The Work:

If it takes Amy 2.5 hours to answer 10 essays, it means that on average she answers 4 essays an hour, or 12 essays in 3 hours.  (4 * 3 = 12)

We also know that Thomas answers 8 essays in 3 hours.

If you add those two numbers together (8 + 12 = 20), you get the number of essays that they could answer together in three hours.  Thomas and Amy could answer 20 essays in 3 hours.

The average time that it takes Thomas and Amy working together to answer one essay is found by dividing the number of hours by the number of essays.  3/20 = 0.15 hours.

Because it takes an average of 0.15 hours to answer 1 essay, you can multiply that number by 18 to get the average amount of time it takes them to answer 18 essays.  0.15 * 18 = 2.7 hours.

Answer 3

Add the numbers you already have!

10+8=18!

Answer 4

i would say 3 hours because they are working together so you wouldnt add up the times seperate.

Answer 5

you don't want to add the number of essays, you want to add the numbers of hours each takes to complete their essays because together they each do18 essays, which is what you're looking for.

2.5 + 3 = 5.5 hours