Question

how many numbers from 0 to 45 have a remainder of 2 when divisible by 4​

Answer 1

Answer:

Let x be your number, let y be its remainder when divided by 45.

Since x and y differ by a multiple of 45, and each multiple of 45 is also a multiple of 5 and a multiple of 9, x and y have the same remainders when divided by 5, and also when divided by 9.

So what you need to do is find the remainders of x when divided by 5 and by 9, and then find the number y between 0 and 44 that has the same remainders.