Percentages Toolkit (Cambridge O Level Maths)

Increase 42 by 16%. 

Write $1.92 as a percentage of $1.60.
 

 ............................................. % 

Increase $22 by 15%.

$ ................................................. 

Bill's weight decreases from 64.8 kg to 59.3 kg.

Calculate the percentage decrease in Bill's weight.
Give your answer correct to 3 significant figures.

George wants to watch all 23 games that a football team will play at home next season.

He can buy

     a season ticket costing £425
or 23 separate tickets costing £24 each ticket.

What percentage of the total cost of 23 separate tickets does George save by buying a season ticket?

Emily buys a pack of 12 bottles of water.
The pack costs £5.64

Emily sells all 12 bottles for 50p each.

Work out Emily's percentage profit.
Give your answer correct to 1 decimal place.

In 2019 Nicole’s annual income was $22 000.
She spent $7200 on accommodation in 2019.

Calculate the percentage of her income she spent on accommodation.

Her annual income of $22000 increased by 4% in 2020.
Calculate her annual income in 2020.

..........................%[2]

$ .......................... [2]

$ ......................... [2]

The table shows the surface area of some countries and their estimated population in 2017.

Find the surface area of France as a percentage of the surface area of China.

 ............................................. %

The population of the Earth in 2017 was estimated to be 7.53 × 10⁹.

The population of the Earth in 2000 was estimated to be 6.02 × 10⁹.

Work out the percentage increase in the Earth’s estimated population from 2000 to 2017.

 ............................................. %

One month, Gretal spent a total of $360 on presents.
She spent  of this total on presents for her parents.
She spent  of the remaining money on presents for her friends.
She spent the rest of the money on presents for her sisters.

Calculate the percentage of the $360 that she spent on presents for her sisters.

............................................. % 

Dhanu has a model railway.

He has a train that consists of a locomotive and 4 coaches.
The mass of the locomotive is 87 g and the mass of each coach is 52 g.

.............................................. g [2]

............................................. % [1]

Manjeet uses 220 litres of water each day.
She reduces the amount of water she uses by 15%.

Calculate the number of litres of water she now uses each day.

......................................... litres

Marianne sells photos.
The selling price of each photo is $6.

Marianne makes a profit of $2.25 on each photo.
Calculate her profit as a percentage of the selling price.

............................................%

A company sells boxes to factories.
Fred buys boxes.
The boxes are sold in packs of 1000
Each pack costs £193.86

Fred orders 3 packs of boxes.
He gets a discount on his total order.

The table shows the discount he will get.

Work out the total cost of the order after the discount.
You must show your working.

Mr Watkins needs to buy some oil for his central heating.

Mr Watkins can put up to 1500 litres of oil in his oil tank.
There are already 850 litres of oil in the tank.
Mr Watkins is going to fill the tank with oil.

The price of oil is 67.2p per litre.
Mr Watkins gets 5% off the price of the oil.

How much does Mr Watkins pay for the oil he needs to buy?

The table gives some information about student attendance at a school on Friday.

The school has a target of 94% of students being present each day.

Did the school meet its target on Friday?

Claire is making a loaf of bread.

A loaf of bread loses 12% of its weight when it is baked.

Claire wants the baked loaf of bread to weigh 1.1 kg.

Work out the weight of the loaf of bread before it is baked.

A force of 70 newtons acts on an area of 20 cm²

pressure =

The force is increased by 10 newtons.
The area is increased by 10 cm²

Helen says,

"The pressure decreases by less than 20%"

Is Helen correct?
You must show how you get your answer.

The cost of a Premium ticket is reduced from $114 to $96.90.

Calculate the percentage reduction in the cost of a ticket.

 ............................................. %

The selling price of a shirt is $26.50.
This includes a tax of 6%.

Calculate the price of the shirt before the tax was added.

$ .................................................

Adil and Brian are paid the same wage.
Adil is given a 7% pay decrease and his new wage is $427.80.
Brian is given a 7% pay increase.
 
Work out Brian’s new wage.
 

$ ................................................ 

Arjun earned $36 515 in 2019.
This was an increase of 9% on his earnings in 2018.

Work out his earnings in 2018.

$ ................................................

In a sale the original prices are reduced by 15%.
 
Calculate the original price of a jacket that has a sale price of $38.25.
  

$ .................................................

In September the total income at a campsite was $37 054.
This was a decrease of 4.5% on the total income in August.

Calculate the total income in August.
 

$ .................................................

The cost of a railway magazine increases by 12.5% to $2.70.

Calculate the cost of the magazine before this increase.

$ .................................................

In a sale, Ali buys a television for $195.80.
The original price was $220.

Calculate the percentage reduction on the original price.

................................................ %

In the sale, Mo buys a jacket for $63.
The original price was reduced by 25%.

Calculate the original price of the jacket.

$ ...................................................

Shona buys a chair in a sale for $435.60.
This is a reduction of 12% on the original price.

Calculate the original price of the chair. 
 

$ ............................................... 

The price of a newspaper increased from $0.97 to $1.13 .
 
Calculate the percentage increase.
 

........................................... %

There were passengers that made a journey in 2018.
This was a 12% decrease in the number of passengers that made this journey in 2017.

Find the number of passengers that made this journey in 2017.
Give your answer in standard form.

In a sale, Marianne buys a new camera for $483.
This is a reduction of 8% on the original price.
 
Calculate the original price of the camera.
 

$ ..............................................

............................................ % [3]

........................... litres/second [3]

The price of a house decreased from $82 500 to $77 500.

Calculate the percentage decrease.

............................................ %

In 2017, the membership fee for a sports club was $79.50.
This was an increase of 6% on the fee in 2016.

Calculate the fee in 2016.

$ ..............................................

A company makes biscuits at a cost of $1.35 per packet.
These biscuits are sold for $1.89 per packet.

............................................ % [3]

$ ................................................ [3]

Rowena buys and sells clothes.

The selling price of dress fabric is $2.97 per metre, which is an increase of 8% on the cost price.
  
Calculate the cost price.
 

$ ............................... per metre

In 2003, Jerry bought a house.

In 2007, Jerry sold the house to Mia.
He made a profit of 20%

In 2012, Mia sold the house for £162 000
She made a loss of 10%

Work out how much Jerry paid for the house in 2003

Marie invests £8000 in an account for one year.
At the end of the year, interest is added to her account.

Marie pays tax on this interest at a rate of 20%
She pays £28.80 tax.

Work out the percentage interest rate for the account.