15e Proportional Reasoning

Hamad needs to mix 7 parts of black paint with 4 parts of white paint to make grey paint. If he has 30 litres of black paint, how many litres of white paint does he need?

Hint: write the ratio of black : white in the form 1 : n first

You do not need to write the units for your answer, but round your answer to 1 decimal place.

(a)  

A shop holds a sale where all items are reduced by the same rate. A pair of trainers goes from $120 to $79.20. A pair of football boots costs $49.50 in the sale. How much did they cost originally?

Hint: write your ratio of prices (original : sale) in the form n:1 first.

MAKE SURE TO INCLUDE YOUR UNITS

(a)  

Which of the following is the ratio of lengths from the original to the enlarged shape?

Take a note of this ratio as it will help you in the next two questions.

• 5 : 9

• 5 : 8

• 5 : 13

Using the ratio you found in the previous question, find the length of x.

Round your answer to 1 decimal place. You do not need to write your units.

(a)  

Using the ratio you found in the previous question, find the length of y.

Round your answer to 1 decimal place. You do not need to write your units.

(a)  

A ship sails across the Pacific Ocean. It has an average speed of 31 miles per hour. It uses 1 litre of fuel for every 2.4 feet it travels.

To the nearest litre, how much fuel does the ship use travelling for one hour?

You do not need to write your units.

(a)  

A ship sails across the Pacific Ocean. It has an average speed of 31 miles per hour. It uses 1 litre of fuel for every 2.4 feet it travels.

To the nearest litre, how much fuel does the ship use travelling for 4,300km?

You do not need to write your units.

(a)  

Henry fills a glass with blackcurrant cordial and water in the ratio 1 : 4. He drinks  $\frac{1}{4}$  of the drink, then fills it back up with water. What is the new ratio of cordial to water?

• 3 : 20

•  $\frac{1}{4}:\ 1$  

•  $\frac{3}{4}:\ 3$  

•  $\frac{1}{4}:\ 4$  

It takes 4 men, 4 hours to dig 4 holes.

How long would it take 16 men to dig 16 holes?

• 4

• 16

• 2

• 8