Before Regrouping: 31 = 3 tens + 1 one After Regrouping: 31 = 2 tens + 11 ones Subtract: Take away 4 ones --> 2 tens + 7 ones = 27
Before Regrouping: 44 = 4 tens + 4 ones After Regrouping: 44 = 3 tens + 14 ones Subtract: Take away 5 ones --> 3 tens + 9 ones = 39