Mental Arithmetic

Mental arithmetic gets faster when you stop calculating digit by digit and start using friendly numbers.

Add by making tens: 47 + 28 becomes 47 + 3 + 25 = 75.

Subtract by counting up: for 83 − 68, count 68 → 70 → 83, so the answer is 2 + 13 = 15.

Multiply by splitting: 7 × 14 = 7 × 10 + 7 × 4 = 98.

Divide by thinking in multiples: 96 ÷ 8 asks "8 times what is 96?" — 8 × 12 = 96.

Now apply them below. The problems get harder as your score rises.