31 Divided by What Equals 90?
Methods
Setting up the problem:
In a problem like this, the “what” means that we’re working with a variable. The most common variable used in math is “x”. So we could say what number, x can we divide 31 by to equal 90?
Solving 31 Divided by What Equals 90
Here’s how you would set up this question as an equation:
31
x
=
90
\frac{31}{x} = 90
x 31 = 90
The goal of the problem is to solve for x. To do this we need to change the equation so that x is alone on one side of the equation.In this case, it can be done in two steps. The first step is to multiply both sides by x to isolate 31:
31
=
90
∗
x
31 = 90*x
31 = 90 ∗ x
Then we can isolate x on the right side of the equation by dividing both sides by 90:
31
90
=
x
\frac{31}{90} = x
90 31 = x
When we simplify the new equation, we can solve for x. In this example, we will round to the nearest three decimal places if that’s needed.
x
=
0.344
x = 0.344
x = 0.344
Practice Other Division Problems Like This One
If this problem was a little difficult or you want to practice your skills on another one, give it a go on any one of these too!
What divided by 23 equals 28?
57 divided by what equals 1?
What is 8/17 divided by 14?
What is 18/16 divided by 15/12?
What is 3 divided by 7/11?