Johnny spent 1/4 of his money on a new belt. 1/5 of it on a soda and $50 cake. If he had $85 left, how much money did he start with?

Question

Kindly give me an equation here in arriving the answer. Thanks

Answer 1

Let M = amount of money started with

 

(1/4)M + (1/5)M + 50 + 85 = M

 

M/4 + M/5 + 135 = M

 

5M/20 + 4M/20 + 135 = M

 

9M/20 + 135 = M

 

135 = M - 9M/20

 

135 = 11M/20

 

M = 135(20/11) = $245.45

Answer 2

Let X = money he started with

 

(1/4)X is money spent on belt

 

(1/5)X is money spent on soda

 

(1/4)X + (1/5)X + $50 = X

 

Can you work it from there?

 

Hint: Multiply all terms by L.C.D. to clear the fraction.

 

If you need help, just let me know.