516 is the dividend, 3 is the divisor, 172 would be the quotient.
3 goes into 5 once with a 2 remainder, that 2 turns into 21 because of the 1 in 516 which 3 goes into seven times with a remainder of zero turning into 6, which 3 goes into twice, making the quotient 172.
172 times 3 is 516