Long division (by two digits)

To divide by a two-digit number, round the divisor to the nearest ten to guess the quotient. Then multiply back and adjust. 158 ÷ 23: think of 23 as 20. 20 × 7 = 140, so try 7. But 23 × 7 = 161, which is more than 158. That's too big, so try 6: 23 × 6 = 138, 158 − 138 = 20. 20 is less than 23, so the quotient is 6 and the remainder is 20. A two-digit number times a one-digit number splits easily: 23 × 6 = 20 × 6 + 3 × 6 = 120 + 18 = 138. If the quotient has two digits, try the tens first. 936 ÷ 12: 12 × 70 = 840, 936 − 840 = 96, 12 × 8 = 96, 70 + 8 = 78, so the quotient is 78. Another way is written division. Start from the highest place, guess a quotient, multiply back and take away. Each question tells you whether it wants the quotient or the remainder. If it divides exactly, it wants the quotient.