312÷15 = 20 remainder 12
12 R 12
15 times.
15 will go into 42 two times with 12 left over.
180 / 15 = 12
18
180 / 15 is equal to 12.
15 goes into 31 twice with a remainder of 1.
12
15 times, remainder 10
12 times
14 times... without using a calculator !how many times does 15 go into 210