# Targeting Grade C Number Unit 3 Long Multiplication Division and Estimation GCSE Mathematics.

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Targeting Grade C Number Unit 3 Long Multiplication Division and Estimation GCSE Mathematics

TOP 1: Review 1 - some multiplication/division Practice 1: Long multiplication Practice 2: Division problems TAIL 1 TOP 2: Review 2 – rounding to significant figures and decimal places Practice 3: Estimating values and rounding solutions TAIL 2 Can you: Solve long multiplication Solve problems with division Try a Quick Test Estimate solutions Round to a given number of significant figures or decimal places Try a Quick Test If not you need

TOP 1: Solve (1)27  7 (2)66  3 (3)752  11 (4)12  243 (5)145  5 (6)291  3 (7)126  4 (8)468  8 Lesson

Practice 1: Solve the following, showing all your working. (1)(a)156  15..........................…(3) (b)237  24..........................…(3) (c)753  63..........................…(3) Solve these problem, showing your working. (2)(a)Tom buys 67 cameras at £312 each. Work out the total cost................................. (3) (b)Carol spends £2.80 on each of her class. She has 25 students. How much does she spend in total?....................................... (3) Lesson

Practice 2:Solve the following, showing all your working. (1)(a)356  24……………………… (3) (b)835  27...……………………. (3) (c)423  19……………………… (3) Solve these problems, showing your working. (2)(a)Tim paid £5.44 for 17 pencils. Each pencil costs the same. Work out the cost of each pencil.……………………… (3) (b)Sophie has £126 to share between her 16 friends. How much do they each get?……………………… (3) Lesson

Mrs. Evans decides to take 863 students on a trip to Euro Disney. They travel by coach. Each coach can hold up to 51 students. In this part of the question you MUST NOT use a calculator. You MUST show ALL your working (a)Work out the smallest number of coaches Mrs. Evans should book so that all the students can go on the trip. (3 marks) Each student has to pay £37 for the trip. 745 students decide to go on the trip. In this part of the question you MUST NOT use a calculator. You MUST show ALL your working (b)How much money is collected if all 745 students pay £37 each. (3 marks) TAIL 1 Next Are you ready for the answers ?

Answers (a)863  51 = 16 r 47, so 17 coaches. (b)745  37 = £27 565 Lesson

TOP 2: Round the following to the number of decimal places given in the brackets. (1)15.645 (2 d.p.) (2)18.756 (1 d.p.) (3)65.95 (1 d.p.) (4)99.997 (2 d.p.) Round the following to the number of significant figures given in the brackets. (1)26.4 (1 s.f.) (2)164.8 (2 s.f.) (3)87.954 (3 s.f.) (4)0.00346 (2 s.f.) Lesson

Practice 3: By using approximation answer the following questions: (1)Tom buys 67 cameras at £312 each. Write down two numbers you could use to get an approximate answer to your calculation. (2)Tom uses his calculator to multiply 17.8 by 0.97. His answer is 18.236. Without finding the exact value of 17.8  0.97, explain why his answer must be wrong. (3) Sally estimates the value of 42.8  63.7to be 8. 285 Write down three numbers Sally could use to get her estimate. …………  ………… ………… Lesson

TAIL 2 Lesson 1 2 3 4 5 6 7 8 9 10 80  3 Write 0.000 726 9 correct to 3 s.f. 96  2 Write 37 451 correct to 1 s.f. 215  5 65  3 Write 12.564 correct to 2 d.p. 412  24 734  16 Write 15.9504 correct to 3 d.p. 240 0.000727 48 40 000 43 195 12.56 9888 45 r 14 15.950 Are you ready for the answers?