Problem from Math Review

GRE Quant Problem Solving
1

I have solved it using choosing numbers can anyone help me with any other way (quicker) or solving using the formula:

reminder = dividend- (divisor * quotient)

Thanks in advance!

Capture
Capture782×77 11.1 KB

2

Any multiple of 3 can be generalized as 3 x k where k is some positive integer value and similarly any multiple of 5 can be generalized as 5 x m where m is again some positive integer value.

Now let the number we are interested in be N, since it leaves a remainder of 2 when divided by 3, it should follow that N is of the form 3k + 2 and since N again leaves a remainder of 1 when divided by 5 it should follow that N is of the form 5m + 1. Since they are both the same number we can equate 3k + 2 to 5m + 1 and since they are asking for the least value, you can start putting in 1,2,3… for k and m and see that 11 meets the criteria.

Now, is this faster? Idk, but it sure beats randomly picking numbers and seeing what sticks because we atleast have a template in form of 3k+2 and 5m+1

1 Like
3

Thanks for the help!