What is x when 45 divided by x equals 21?

In other words, what would the divisor be if the dividend were 45 and the quotient 21?

To find the answer, just divide the dividend by the quotient: 45 ÷ 21 = 2.1428571428571

To prove this, let's compute 45 divided by 2.1428571428571: 45 2.1428571428571 = 21

How does it work?

Asking what the value of x could be when 45 divided by x gives a result of 21, is equivalent to solving the following equation:

45 x = 21

  1. Multiply both sides by x: 45 x x = 21 x
  2. 45 x x is equivalent to x x × 45 , which simplifies to 1 × 45 (or just 45 ).
  3. Thus, the equation becomes: 45 = 21 x
  4. To find x, divide both sides by 21: 45 21 = 21 x 21
  5. Which gives, after simplification: 2.1428571428571 = x (or x = 2.1428571428571 )

So, if the dividend is 45 and the quotient is 21, the divisor is 2.1428571428571.