Question 1
Find the percentages of the following:
1(a) 40\% of 120
ANSWER: Simple text answer
Answer: 48
Workings:
\dfrac{40}{100} \times 120 = 48
Marks = 1
1(b) 80\% of 800
ANSWER: Simple text answer
Answer: 640
Workings:
\dfrac{80}{100} \times 800 = 640
Marks = 1
1(c) 70\% of 230
ANSWER: Simple text answer
Answer: 161
Workings:
\dfrac{70}{100} \times 230 = 161
Marks = 1
1(d) 99\% of 130
ANSWER: Simple text answer
Answer: 128.7
Workings:
\dfrac{99}{100} \times 130 = 128.7
Marks = 1
1(e) 28\% of 900
ANSWER: Simple text answer
Answer: 252
Workings:
\dfrac{28}{100} \times 900 = 252
Marks = 1
Question 2
Tommy went to the shop where there was a 20\% off sale taking place.
The shirt he wanted to buy was originally \pounds20.
How much money does he save in the sale?
ANSWER: Simple text answer
Answer: \pounds 4
Workings:
0.8 \times \pounds20 = \pounds16
\pounds20 - \pounds16 = \pounds4
Marks = 2
Question 3
A bike costs £350[/latex] but is reduced by 35\%.
What does the bike cost after the reduction?
ANSWER: Simple text answer
Answer: £227.50
Workings:
0.65 x £350 = £227.50
Marks = 2
Question 4
In a school of 600 pupils, 64% walk to school regularly.
How many pupils walk to school regularly?
ANSWER: Simple text answer
Answer: 384
Workings: 0.64 \times 600 = 384
Marks = 2
Question 5
Tommy buys a rare painting for £3200.
He eventually sells it for £3800.
Work out the percentage increase in value of the painting.
ANSWER: Simple text answer
Answer: 18.75
Workings:
\dfrac{3800}{3200} = 0.1875
0.1875 \times 100 = 18.75\%
Marks = 2
Question 6
Jane fills her empty car with 12 litres of petrol.
After driving for the day the car now has 7.5 litres of petrol in the tank.
Calculate the percentage decrease of petrol in the car.
ANSWER: Simple text answer
Answer: 37.5\%
Workings:
\dfrac{7.5}{12} = 0.625
1 - 0.625 = 0.375 so 37.5\%
Marks = 2
Question 7
A speed boat travels from A to B for the first part of a journey and then B to C to complete a journey.
For the entire journey, A to C, the boat travels at an average speed of 21 kmph.
During the journey, from B to C, the boat only travels at a speed of 13 kmph.
Calculate the percentage decrease in average speed between the first and second part of the journey, given that the distance off each part is equal.
ANSWER: Simple text answer
Answer: 55.2
Workings:
\dfrac{13 + x}{2} = 21 so x = 29 kmph
\dfrac{13}{29} = 0.448 so percentage decrease = 1 - 0.448 = 0.552
Marks = 3