Question

If you take a certain number 2.5 times then add 1.75 and divide the result by 0.8, you’ll get 37.5. What was the original number?
Please show how you did it!

Answer 1

 lets take the certain number and call it 'x'
take 2.5 of the number = 2.5x
when we add 1.75 -   2.5x + 1.75
and divide by 0.8  -    (2.5x+ 1.75)/0.8
the answer is 37.5
lets construct an equation with this information
(2.5x + 1.75)/0.8 = 37.5
2.5x + 1.75 = 37.5* 0.8
2.5x = 30 - 1.75
2.5x = 28.25
x = 28.25/2.5
x = 11.3

Answer 2

The answer is 11.3. You just take all the directions and you do the opposite operation. 

Work

Step 1 - 37.5 x 0.8 = 30

Step 2 - 30 - 1.75 = 28.25

Step 3 - 28.25 divided by 2.5 = 11.3.

Step 4/ Final Answer - 11.3