What an arithmetic expression is

Every visiting relative asks you: What is 20 + 3? What is 20 − 4? Next time, ask them back: *Do you know what 20 − 4 is called?* It is an arithmetic expression: a maths phrase like 13 + 2, 20 − 4, 12 × 5 or 18 ÷ 3.

Every expression has a value: the single number it works out to. The value of 13 + 2 is 15. We join them with =: 13 + 2 = 15.

You can read an expression aloud in more than one way. 13 + 2 is 13 plus 2 or the sum of 13 and 2. 5 × 25 is 5 times 25 or the product of 5 and 25.

Expressions are how we write a situation down. Mallika spends ₹25 on lunch at school every day. From Monday to Friday that is 5 × 25: five days, ₹25 each.

Different expressions can have the same value. 12 = 10 + 2 = 15 − 3 = 3 × 4 = 24 ÷ 2 = 9 + 3 = 48 ÷ 4 ... There is no end to them. So an expression and its value are not the same thing.

Pick your favourite number and write as many expressions for it as you can.