What is x when 9 divided by x equals 21?

In other words, what would the divisor be if the dividend were 9 and the quotient 21?

To find the answer, just divide the dividend by the quotient: 9 ÷ 21 = 0.42857142857143

To prove this, let's compute 9 divided by 0.42857142857143: 9 0.42857142857143 = 21

How does it work?

Asking what the value of x could be when 9 divided by x gives a result of 21, is equivalent to solving the following equation:

9 x = 21

  1. Multiply both sides by x: 9 x x = 21 x
  2. 9 x x is equivalent to x x × 9 , which simplifies to 1 × 9 (or just 9 ).
  3. Thus, the equation becomes: 9 = 21 x
  4. To find x, divide both sides by 21: 9 21 = 21 x 21
  5. Which gives, after simplification: 0.42857142857143 = x (or x = 0.42857142857143 )

So, if the dividend is 9 and the quotient is 21, the divisor is 0.42857142857143.