[3](a)Calculate (3.2 + 4.7) ÷ (2.1 − 0.9)², giving your answer to 3 significant figures.

[2](a)Explain why it is important to use brackets when entering a fraction like (5+3)/(2+1.5) into a calculator, rather than typing 5+3/2+1.5.

[2](a)Calculate √144 + 3³.

[2](a)Calculate (5.6 − 2.1) × 3.2.

[2](a)Calculate (4.2)² − √(50), giving your answer to 3 significant figures.

[2](a)Explain why it is good practice to write down an estimate before using a calculator for a complex calculation.

[2](a)A calculator shows an answer of 7.999999999 for a calculation you expect to give a whole number. Suggest what has most likely happened, and what you should write as your final answer.

[2](a)Calculate 1/(0.2 + 0.05), giving your answer as a decimal.

[2](a)Calculate √(2.3² + 4), giving your answer to 3 significant figures.

[2](a)Calculate (7 − 2.5) ÷ 1.5², giving your answer as a decimal.