Suppose that the division N/5 leaves a remainder of 4, and the division N/2 leaves a remainder of 1, what is the ones digit on N?

Since N/2 leaves a remainder, N must be odd and ends with 1, 3, 5, 7, or 9.

N/5 also leaves a remainder, so N is not divisible by 5, so it does not end in 5.

The only correct choice is then 9, since

1 = 0•5 + 1 and 1 = 0•2 + 1

3 = 0•5 + 3 and 3 = 1•2 + 1

7 = 1•5 + 2 and 7 = 3•2 + 1

9 = 1•5 + 4 and 9 = 4•2 + 1

Alternatively, the given information is equivalent to saying

Then you can use the Chinese remainder theorem to find N.

u dumb boi

step-by-step explanation:

-2x + 7 = 7

subtract 7 from both sides.

-2x = 0

divide both sides by -2.

x = 0