20 multiplied by a number, decreased by 15 equals 25. How do you find the number?
See full explanation for finding the number below
To solve this world problem we will convert it to a math problem to solve one phrase at a time.
"by a number" - let's call the number
"20 multiplied by a number" or by
"decreased by" means to subtract what follows which in this case is "15" so we can expand what we are writing to:
"equals 25" is the same as
We can now solve: