Question

When 142 is added to a number, the result is 64 more times than 3 times the number. What is the number?

Answer 1

x+142 =3x+64

subtract x from each side

142 = 2x+64

subtract 64 from each side

142-64 = 2x

78=2x

divide by 2

78/2 = x

x=39

The number is 39

Answer 2

$n-the\ number\\\\n+142=64\cdot3n\\\\n+142=192n\qquad\text{subtract n from both sides}\\\\142=191n\qquad\text{divide both sides by 191}\\\\\dfrac{142}{191}=n\to \boxed{n=\dfrac{142}{191}}$

$n+142=3n+64\qquad\text{subtract 142 from both sides}\\\\n=3n-78\qquad\text{subtract 3n from both sides}\\\\-2n=-78\qquad\text{divide both sides ny (-2)}\\\\\boxed{n=39}$