Squares and square roots

MathematicsMiddle school

Squares up to 20 and exact square roots, to be recognised without hesitation.

Cards

Click a card to see its answer. Series no. 571725 — this page’s address gives these exact cards again.

Other series

Adding, subtracting and multiplying signed numbers, where the signs trip up the reflexes.

Turning a simple fraction into its decimal form, in your head, without doing the division.

Solving an equation of the form ax + b = c in your head, with a whole-number solution.

Taking a simple percentage of a number, and recognising an increase or a decrease.

Moving between scientific notation and decimal form, and back, without a calculator.

Expanding (a + b)², (a − b)² and (a + b)(a − b) without going back through distributivity.