OCS CGSE MATHS: 1.1 BASIC CALCULATIONS EXAM (QUESTIONS AND ANSWERS)A+GRADED GUARANTEED PASS

1.1 Basic calculations ©Cambridge University Press and OCR 2021 2 TIP Some questions need to be worked out in stages. Do not be tempted to do the calculations in your head. 4 Subtract the product of 27 and 15 from the sum of 582 and 260. 5 Add the difference between 1201 and 725 to the quotient of 27 divided by 3. 6 Which of the following numbers have a difference of 42 and a product of 4600? a 30 and 72 b 46 and 100 c 50 and 92 7 Charlie bought six pads of paper priced at £1.52 each. He was asked to pay £15.10, which was not correct. Without working out the exact cost, estimate how much he should have paid. Use a calculator for questions 8–11. 8 Nina changed £420 into euros. £1 is worth 1.16 euros. How many euros did she receive? Always look for the command word used in a question to help you work out what you need to do to solve the problem. WORKED EXAMPLE Biscuits can be bought in packets of 20 or 30. All biscuits are identical in size and quality. A 20-biscuit packet costs £1.70. A 30-biscuit packet costs £2.46. Callum asks ‘Which biscuit packet is better value?’ Show your working. Solution Find the cost of one biscuit in each packet. One biscuit in the 20-biscuit packet costs £1.70 ÷ 20 = £0.085 = 8.5p. One biscuit in the 30-biscuit packet costs £2.46 ÷ 30 = £0.082 = 8.2p As 8.2p is less than 8.5p, the 30-biscuit packet is better value. 1.1 Basic calculations ©Cambridge University Press and OCR 2021 3