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Boston St Mary's RC Primary Academy


Boston's Catholic School

Maths

Here are all the activities you will need for your maths learning this week. 

As always, if there are any questions then please feel free to email me at Year5@bostonstmarys.co.uk   

This week our focus is percentages.

You can also use: 

Times tables rock stars

Maths factor

Hit the Button

Twinkl

Here are all the activities you will need for your maths learning this week. 

As always, if there are any questions then please feel free to email me at Year5@bostonstmarys.co.uk   

This week our focus is percentages.

You can also use: 

Times tables rock stars

Maths factor

Hit the Button

Twinkl

 

Challenge: I have made a mistake in a couple of the worksheets- can you tell me where I've gone wrong? The first 3 people to let me know get a merit- good luck!

Monday -Finding percentages of amounts.

In order to find 10% of a number- you must divide the number by 10 (1 d.p to the left)

In order to find 5% you must find 10% and divide it by 2 / halve it

Don’t forget to add them together.

E.g  60% of 320 =

10% --> 320 divided by 10 = 32

60% --> 32 x 6 =192

There are videos on youtube but many of these make it seem much more complicated!

Tuesday – finding 1%

In order to find 10% of a number- you must divide the number by 10 (1 d.p to the left)

In order to find 5% you must find 10% and divide it by 2 / halve it

In order to find 1% you must divide a number by 100 (2d.p to the left)

Don’t forget to add them together.

E.g  66% of 320 =

10% --> 320 divided by 10 = 32               divide by 10 – 1 d.p to the left

60% --> 32 x 6 =192                                       Long multiplication

5% --> 32 divided by 2 = 16

1% --> 320 divided by 100 = 3.2              divide by 100 – 2 d.p to the left

66% --> 192 + 16 + 3.2

= 211.2

Wednesday – Percentage reductions

So you already know how to find a percentage of an amount. Today you are going to be calculating percentage reductions – this means to reduce the number by the percentage amount.

We often see percentage reductions in our daily lives – 50% of clothing, 10% of food that is close to it’s sell-by date etc.

Example

Cat food was £6.60. It has been reduced by 35%. What is the new price?

10% = 0.66p                               (move 1 d.p to the right)

30% --> 0.66 x 3 = £1.98             (long multiplication- remembering decimal place!)

5% --> 0.66 divided by 2 = 0.33

35% --> £1.98 + 0.33 = £2.31

Reduction --> £6.60 - £2.31 = £4.29

Please complete the percentage puzzle activity sheet – Wednesday Maths Activity

Thursday – Percentage increase

So you already know how to find a percentage of an amount and how to reduce an amount by a percentage. Today you are going to be calculating percentage increases – this means to increase the number by the percentage amount.

We often see percentage increases in our daily lives – such as 30% extra free, or 10% increase in test scores etc.

Example

A normal bag of chocolate weights 326g. However, the new bar of chocolate contains 24% more chocolate. What is the new weight of chocolate?

10% = 32.6g                                         (1 d.p to the right)

20% -->  32.6 x 2 = 65.2g

1% --> 326 divided by 100= 3.26g            (2 d.p to the right)

4% = 3.26 x 4 = 13.04g

24% = 65.2 + 13.02 = 78.22g                  (Remember your units and place value)

Please complete the percentage puzzle activity sheet – Thursday Maths Activity

Friday ­– Percentage Word Problems

When completing word problems it is always important to think…

Read – Read the question at least once- you can underline key information

Understand – what is the question asking you to find out?

Calculate – what method/s is/are appropriate?

Solve – carry out your method

Answer – give your answer in the correct units

Check – Can you estimate your answer – does yours seem reasonable or clos? Review your calculation to make sure there are no mistakes

Remember – Word problems can require multiple steps.

Example

A sunflower is measured at the beginning of June and is 40cm tall. The sunflower grows by 25% each month for three months. What height is the sunflower to the nearest centimetre at the beginning of September?

Step 1 – find out what 25% increase of 40 is.

25% of 40 = 10

June - July it has grown by 10cm – so new height is 50cm

 

Step 2 – find out what 25% increase of 50 is.

25% of 50 = 12.5

July - August it has grown by 12.5cm – so new height is 62.5cm

 

Step 3 – find out what 25% increase of 62.5 is

10% = 6.25

20% = 12.5

5% = 3.125

25% = 15.625

August - September it has grown by 15.625cm – so new height is 78.125cm

The question asks us to give our answer to the nearest centimetre so I look at the tenths which is 1. I know I need to round down, so my answer is 78cm.