A boy lost55%of his money . If he had 671/2 left how much was his pocket money.

Let's use the variable "x" to represent the boy's original pocket money.

According to the problem, he lost 55% of his money:

55% of x = 0.55x

That means he had the remaining percentage left:

100% - 55% = 45%

So he had 45% of his original pocket money left, which is represented by the fraction 45/100:

45/100 * x = 67.5

Now we can solve for x by multiplying both sides by 100/45:

x = 67.5 * 100/45

x = 150

Therefore, the boy's original pocket money was $150.