KS3 Revision Questions Number Level 7

Transcription

1 KS Revision Questions Number Level 7. Ratio (a) On this necklace the ratio of black beads to white beads is : How many more black beads do you need to add to make the ratio of black to white :?... black beads Here is the necklace again. How many more black beads and white beads do you need to add to make the ratio of black to white :?... black beads,... white beads. Sorting primes Sophie says: If n represents a prime number, then n + will also represent a prime number. Use an example to explain why she is wrong. St Anselm's College

2 . Sums and products (a) Sandra is thinking of two numbers. Her two numbers have a negative sum, but a positive product. Give an example of what her numbers could be.... and... Mark is also thinking of two numbers. His two numbers have a positive sum, but a negative product. Give an example of what his numbers could be.... and.... Square root (a) Explain why 89 must be between 9 and 0 89 is also between two consecutive whole numbers. What are the two numbers?... and... St Anselm's College

3 . Sequence (a) For each sequence below, tick ( ) the correct box to show if it is increasing, decreasing or neither. increasing decreasing neither marks A different sequence has this expression for the nth term: ( n ) Work out the first four terms in the sequence Cancelling Work out =... ( ( ) ) =... St Anselm's College

4 7. Red and blue cubes In a bag, there are red and blue cubes in the ratio : 7 red : blue : 7 I add 0 more red cubes to the bag. Now there are red and blue cubes in the ratio 6 : 7 red : blue 6 : 7 How many blue cubes are in the bag?... marks 8. Powers Work out the values of m and n 8 = m m =... 8 = n n =... St Anselm's College

5 9. Dissection A square of area 6cm is cut to make two rectangles, A and B. A B Area = 6 c m Not drawn accurately The ratio of area A to area B is : Work out the dimensions of rectangles A and B. Rectangle A:... cm by... cm Rectangle B:... cm by... cm marks 0. Multiplication grids Write the missing numbers in these multiplication grids marks St Anselm's College

6 . Quiz In a quiz game two people each answer 00 questions. They score one point for each correct answer. The quiz game has not yet finished. Each person has answered 90 questions. The table shows the results so far. Person A 60% of the first 90 questions correct Person B 0% of the first 90 questions correct Can person B win the quiz game? Tick ( ) your answer. Show working to explain your answer. B can win. B cannot win but can draw. B cannot win or draw. marks. 6 Here is an equation. x y 6 Give four different pairs of values that satisfy this equation. First pair x... y... Second pair x... y... Third pair x... y... Fourth pair x... y... marks St Anselm's College 6

7 . Sixths A teacher said to a pupil: To the nearest per cent 6 is 7% The pupil said: So, to the nearest per cent, 6 must be % Show that the pupil is wrong.. Powers (a) Write the values of k and m. 6 = 8 = k = m k... m... marks Complete the following: = 768 =... St Anselm's College 7

8 . Juice The table shows a recipe for a fruit drink. Type of juice Amount Orange Cranberry Grape litre litre litre 6 Total litre I want to make litres of the same drink. Complete the table below to show how much of each type of juice to use. Show your working. Type of juice Amount Orange litre Cranberry litre Grape litre Total litres marks St Anselm's College 8

9 6. Egyptians,, are all examples of unit fractions. 8 All unit fractions must have a numerator that is a denominator that is an integer greater than The ancient Egyptians used only unit fractions. For, they wrote the sum + (a) For what fraction did they write the sum +? Show your working They wrote as the sum of two unit fractions. 0 One of them was What was the other? Show your working.... St Anselm's College 9

10 (c) What is the biggest fraction you can make by adding two different unit fractions? Show your working.... marks 7. Rounding (a) Circle the best estimate of the answer to Circle the best estimate of the answer to (c) Estimate the answer to Give your answer to significant figure.... (d) Estimate the answer to St Anselm's College 0