Question

To solve the equation 34x=15, Abby multiplied both sides by ¾ and got a solution of x=1114. Explain the error that Abby made and then find the correct value of x.

Answer 1

x = 20

Explanation:

3/4x = 15

Abby's calculation:

3/4x = 15

Multiply both sides by 3/4

x = 1114

Abby's error was multiplying both sides by 3/4 instead of dividing both sides by 3/4 to get the value of x

Correct calculation:

3/4x = 15

Divide both sides by 3/4

3/4x ÷ 3/4 = 15 ÷ 3/4

x = 15 × 4/3

x = 60/3

x = 20

Check:

3/4x = 15

3/4*20

= (3*20) / 4

= 60/4

= 15

3/4*20 = 15