mark this work is it right or wrong? what is the correct answer?

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Mark this work Is it right or wrong? What is the correct answer?

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Mark this workIs it right or wrong?

What is the correct answer?

1. Tim buys one fibre tip pen and one gel pen.He pays with a £5 note.(a) How much change should he get?Mrs Holt has £20 to spend.(b) Work out the greatest number of roller ball pens she can buy.Mr Davis buys 20 gel pens. 25% of the 20 gel pens do not work.(c) Work out 25% of 20

a.) 2.05 + 2.20 = 4.25

5 - 4.25 = 0.75pb.) 20 ÷ 2.60 = 7.6

She can buy 8 pensc.) 1/4 of 20 = 5

Gel pen £2.20Fibre tip £2.05Roller ball £2.60

2. Imran plays a game of chess with his friend.A game of chess can be won or drawn or lost.The probability that Imran wins the game of chess is 0.3The probability that Imran draws the game of chess is 0.25Work out the probability that Imran loses the game of chess.

0.3 + 0.25 = 0.281- 0.28 = 0.72

3. (a) Solve 4(y+2)=6

(b) Make h the subject of the formula f=g+3h

a.) 4y + 2 = 64y = 4y = 1

b.) f – g = 3hh = f – g ÷ 3

4. The equation x3 + 10x = 51 has a solution between 2 and 3.Use a trial and improvement method to find this solution.Give your answer correct to 1 decimal place.You must show all your working.

x x3 + 10 x

2.5 40.625 Too low

2.7 46.683 Too low

2.8 49.952 Too low

2.9 53.389 Too high

The solution is 2.9

5. Joanna made a list of the ages of the children in a playgroup.

4 3 1 4 2 4 4 2 1 2(a) Find the median age of the children in the play group.(b) Find the range of the ages of the children in the playgroup.

a.) 2 and 4b.) 4 - 1 = 3

6. Three boys shared £48 in the ratio 5:4:3Daniel received the smallest amount.Work out the amount Daniel received.

5 + 4 + 3 = 1248 ÷ 12 = 4Daniel received 4 x 3 = 12

7. Write an expression for the perimeter of the trapezium.Write your answer as simply as possible.

3p

6p

q q

3p + q + 6p + q= 9p + 2q

8. Angela, Barbara and Carol each collect pop star cards.Angela has p cards.Barbara has twice as many cards as Angela.(a) Write down an expression for the number of cards that Barbara has.Carol has 7 cards less than Angela.(b) Write down an expression for the number of cards that Carol has.

a.) Barbara has 2pb.) 7 - p

9. There are 3 red pens, 4 blue pens and 5 black pens in a box.Sameena takes a pen, at random, from the box.Write down the probability that she takes a black pen.

5/7

10. The radius of this circle is 8 cm.Work out the circumference of the circle.Give your answer correct to 2 decimal places.

8cm

C = πd= 3.142 x 8= 25.136= 25.13 (to 2

dp)

11. Use your calculator to work out22.4 x 14.5

8.5 x 3.2Write down all the figures on your calculator display.

122.2776471

12. (a) Andy sells CDs.He sells each CD for £8.80 plus VAT at 17 %.How much VAT does he pay?(b) A car tyre costs £80 plus VAT at 17 %.Work out the total cost of the tyre.

a.) 17% of 8.80 = £1.496b.) 17% of £80 = £13.6£80 + £13.6 = £93.60

13. A year ago, Daniel’s height was 1.24 metres.Daniel’s height has now increased by 9.5%.Work out Daniel’s height now.Give your answer to an appropriate degree of accuracy.

9.5% of 1.24 = 0.1178Daniels height = 1.24 + 0.1178 = 1.3578 or 1.36m

14. S = 1/2 at2

Find the value of S when t = 3 and a =1/4

S = 0.5 x 1/4 x 32

S = 0.5 x 0.25 x 6S = 0.75

15. ABC is a right-angled triangle.AB = 7 cm,AC = 11 cm.Work out the length of BC.Give your answer correct to 2 decimal places.

7cm11cm

A

B C

112 + 72 = 121 + 49= 171171 ÷ 4 = 42.75

ANSWERS

1. Tim buys one fibre tip pen and one gel pen.He pays with a £5 note.(a) How much change should he get?Mrs Holt has £20 to spend.(b) Work out the greatest number of roller ball pens she can buy.Mr Davis buys 20 gel pens. 25% of the 20 gel pens do not work.(c) Work out 25% of 20

a.) 2.05 + 2.20 = 4.25

5 - 4.25 = £0.75pb.) 20 ÷ 2.60 = 7.6

She can buy 7 pensc.) 1/4 of 20 = 5

Gell pen £2.20Fibre tip £2.05Roller ball £2.60

2. Imran plays a game of chess with his friend.A game of chess can be won or drawn or lost.The probability that Imran wins the game of chess is 0.3The probability that Imran draws the game of chess is 0.25Work out the probability that Imran loses the game of chess.

0.3 + 0.25 = 0.551- 0.55 =0.45

3. (a) Solve 4(y+2) = 12

(b) Make h the subject of the formula f=g+3h

a.) 4y + 8 = 124y = 4y = 1

b.) f – g = 3hh = (f – g) ÷ 3

4. The equation x³ + 10x = 51 has a solution between 2 and 3.Use a trial and improvement method to find this solution.Give your answer correct to 1 decimal place.You must show all your working.

x x³ + 10 x

2.5 40.625 Too low

2.7 46.683 Too low

2.8 49.952 Too low

2.9 53.389 Too high

The solution is 2.8

5. Joanna made a list of the ages of the children in a playgroup.

4 3 1 4 2 4 4 2 1 2(a) Find the median age of the children in the play group.(b) Find the range of the ages of the children in the playgroup.

1 1 2 2 2 3 4 4 4 4a.) 2.5b.) 4 - 1 = 3

6. Three boys shared £48 in the ratio 5:4:3Daniel received the smallest amount.Work out the amount Daniel received.

5 + 4 + 3 = 1248 ÷ 12 = 4Daniel received 4 x 3 = 12

7. Write an expression for the perimeter of the trapezium.Write your answer as simply as possible.

3p

6p

q q

3p + q + 6p + q= 9p + 2q

8. Angela, Barbara and Carol each collect pop star cards.Angela has p cards.Barbara has twice as many cards as Angela.(a) Write down an expression for the number of cards that Barbara has.Carol has 7 cards less than Angela.(b) Write down an expression for the number of cards that Carol has.

a.) Barbara has 2pb.) p - 7

9. There are 3 red pens, 4 blue pens and 5 black pens in a box.Sameena takes a pen, at random, from the box.Write down the probability that she takes a black pen.

5/12

10. The radius of this circle is 8 cm.Work out the circumference of the circle.Give your answer correct to 2 decimal places.

8cm

C = πd= 3.142 x 16= 50.272= 50.27(to 2

dp)

11. Use your calculator to work out22.4 × 14.5

8.5 × 3.2Write down all the figures on your calculator display.

(22.4 x 14.5)÷(8.5 x 3.2)

= 11.94117647

12. (a) Andy sells CDs.He sells each CD for £8.80 plus VAT at 17 %.How much VAT does he pay?(b) A car tyre costs £80 plus VAT at 17 %.Work out the total cost of the tyre.

a.) 17% of 8.80 = £1.50b.) 17% of £80 = £13.6£80 + £13.6 = £93.60

13. A year ago, Daniel’s height was 1.24 metres.Daniel’s height has now increased by 9.5%.Work out Daniel’s height now.Give your answer to an appropriate degree of accuracy.

9.5% of 1.24 = 0.1178Daniels height = 1.24 + 0.1178 = 1.3578 or 1.36m

14. S = ½ at²Find the value of S when t = 3 and a = ¼

S = 0.5 x ¼ x 3²S = 0.5 x 0.25 x 9S = 1.125

15. ABC is a right-angled triangle.AB = 7 cm,AC = 11 cm.Work out the length of AC.Give your answer correct to 2 decimal places.

7cm11cm

A

B C

11² - 7² = 121 - 49= 72 √72=8.48528... = 8.49