Category: Maths Resources

Year 3 mental arithmetic: sets 29 and 30

This week the questions are all in the form of word problems. Generally children find these harder than just ‘sums’ because they are not told what operation needs to be carried out to reach the correct answer. Indeed, sometimes it can be tricky. Looking at the question,

‘I think of a number and subtract 10. The answer is 27. What is my number?’

Immediately the word subtraction will come to mind as it is used in the question. But, in fact, an addition has to be done to find the correct answer.

Several questions also require a good knowledge of the 2x, 5x and 10x tables.

If you are reading these out for children to answer be sure to read each question slowly and at least twice. The first time the question is heard the child will probably be thinking about what needs to be done. The second time reinforces the numbers involved.

Year 3 mental arithmetic (sets 29 and 30)

Year 2 number challenge

Open ended questions are an excellent way to reinforce mathematical concepts, practice number skills and find out about some of the amazing patterns in maths. This maths worksheet is posted in our Year 2 category, under Using and Applying Maths and has proved to be one of our most popular resources.

The problem is to find as many ways as possible to make a total of 12 using three of the numbers on the cards. (Cards cannot be used twice in the same total so 4, 4 and 4 would not be allowed.)

It would be a good idea to have some cards printed with the digits on so that they can be cut out to help with this. They are available in the reception maths worksheets section.

Plenty of practice here at adding three small numbers. Also encourage working in a logical order and setting out results in a clear, logical way. There is no reason why recordings cannot be made of totals that are not 12.

Again plenty of opportunity for talking about the numbers and what counts as a different way. Is 1 + 2 + 9 the same as 2 + 1 + 9 ?

Make 12

KS2 maths 2011 paper B question 4

We continue our look at the KS2 Maths 2011 Paper B with this question, which should be an easy 2 marks, but all too often little errors are made when using a calculator.

Two marks awarded for all four rows correct.

One mark awarded for 3 out of 4.

No marks for 2 or less correct.

Other clear indications of the answer, such as a cross or Y will also gain the mark.

Suggested method:

The key to answering this question is to remember that a calculator is available and to take each pair of questions separately.

Children should be able to use the keys properly. They should know how to clear the calculator, how to enter numbers and operations and how to read the results. Interpreting the results is also important and it is essential to look at the answer to check that it is sensible – within a range of what is expected.

For example 34 x 21 is going to be around 600 or 700.

With these questions it is a good idea to jot down each of the two answers and then compare them. It is essential that the calculator is cleared after each calculation.

Question 4 from SAT Paper B 2011

Question 4 answers and suggested method 2011 paper B

 

Year 5 addition: missing digits

On the face of it this might look like an easy page, but in fact many children find this quite tricky. It should not be tried until children have a good grasp of the standard written method of addition.The addition calculation has been laid out in the standard way, together with the answer. However, two of the digits in the sum are missing. Sometimes it is easy to find the missing digit, but not always, especially when tens have been ‘carried’ into hundreds.

If children get this page correct it shows a good understanding of the standard method of addition. If they struggle it would be well worth looking again at this method.

This page can be found in the Year 5 Calculating category.

Addition: missing digits

Year 3 mental arithmetic: addition and subtraction

This week’s sets of mental arithmetic questions concentrate solely on addition and subtraction. There are many different strategies that can be used, depending very much on the numbers involved.

For example:

7 plus 147 can be done quickly by counting on 7, or by  knowing off by heart that 7 and 7 is 14

9 plus 129 can be done by adding 10 and subtracting 1

44 plus 16 can be done by adding the tens first and then the units, or vice versa.

It is important that children have all these techniques at their fingertips, and one way to make sure they have is to point out the many possible ways and which are the most efficient.

Year 3 mental arithmetic (sets 27 and 28)

 

More addition of money

I am often asked to provide more pages of addition ‘sums’ so here is another look at using the standard method of addition for money.

The first eight questions are laid out in the correct way. The next seven need to be written in the same way, with the decimal points lining up in a vertical line.

With these questions there is ‘carrying’ from both the hundredths to the tenths and from the tenths to the whole pounds.

If this page is sent as homework look for clues that the answers have been done on a calculator. All working should be shown, including the smaller ‘1’ below the answer line. Also question 10 should be answered as £10.00 rather than just £10.

There is no harm in using a calculator to check that the answers are correct, but the main purpose of pages like these is to give practice and reinforcement of the written method.

This page and other similar pages can be found in the Four Rules category, under Addition.

Standard money addition (p3)

KS2 Maths 2011 Paper B: Question 3

Symmetry is a very popular subject with the SAT writers and can be an easy way to pick up a couple of marks.

For this question two marks are awarded for all three lines of symmetry drawn correctly.
One mark awarded for two diagrams completed correctly.
No marks for just one marked correctly.
Slight inaccuracies in drawing can be allowed, provided the intention is clear. A ruler should be used.
Suggested method:
This is very much a case of using the resources that you have been provided with and recognising how they can be useful.

A mirror is certainly helpful for this question. Placing it where it is thought the line of symmetry should be and looking to see if the reflection matches the drawing. When working out where the lines should go imagine that they are folded along the line and completely overlap each other. Some children will find this very tricky, especially as two of the lines of symmetry are not horizontal or vertical.
Alternatively, use tracing paper to draw the diagrams and then fold so that the two sides completely overlap. Draw the line where the fold is. Tracing paper is often provided in the test.

Question 3

Question 3 answer and suggested method 2011 paper B

Year 3 mental arithmetic for spring term

Today I have published the first of our next sets of mental arithmetic for year 3. This is the first of another 12 sets for the spring term, which will build up to another 24 pages of 10 questions.

This week I am looking at rounding, using terms such as ‘more than’ and ‘less than’ as well as finding numbers half way between two other numbers.

The rounding questions are straightforward and a good check to see if children understand this idea.

Watch out for the question, ‘500 is 100 more than which number?’ Many children will not think how this has been phrased and answer 600, when the correct answer is 400.

Finding ten less than a number which is just over the hundreds boundary (eg ten less than 207) can also prove tricky. There are several approaches, including

Taking ten from the 20 tens in 207, leaving 19 tens and 7 or 197.

Counting back 7 to 200 and then another 3 to 197.

Remember to ask children how they worked out the answers.

Year 3 mental arithmetic: (sets 25 and 26)

KS2 Maths SAT questions and answers: Paper B 2011

This is the first in a new series looking at SAT papers, the questions, answers and best methods of going about them. This term I am looking at the 2011 Paper B. Calculators are allowed for this paper, but generally I think that paper B tends to be harder than Paper A.

The first question has 5 numbers and asks which is the nearest to 100.

1.   The number 111 should be circled.
One mark for this question.
Other clear indications of the answer, such as underlining or ticking will also gain the mark.
Suggested method:
This is probably best done by a process of elimination.

909 can immediately be crossed off as it is so far from 100.

This leaves 70 and 85 below 100
and 111 and 120 above 100.

Immediately it can be seen that 85 is nearer to 100 than 70 and that 111 is nearer than 120.
So that leaves 85 and 111.

85 is 15 away from 100. 111 is 11 away from 100 so the answer must be 111.

2. 10 + 30 = 40

20 + 30 = 50

One mark for this question.
Calculations may be given in either order.

 

The first two numbers within each calculation may be given in either order.
Suggested method:
A quick glance at the numbers on the cards will suggest that the answer cards are likely to have the two highest numbers in them. That’s 40 and 50.
50 can be made from 30 and 20. This leaves 30 and 10 to make 40.

A calculator is not really of any help with these two questions.

2011 Paper B Question 1 and 2

Question 1 and 2 answers and suggested method 2011 Paper B

 

Christmas present buying worksheet

Here we have an open-ended page to keep up the Christmas theme for this week.

More Christmas themed worksheets can be found at;

http://pages.urbrainy.com/happy-christmas-2011

There are four items with prices; a set of beads for £2, a box of chocolates for £3, a bag for £5 and a bottle of perfume for £7.

The task is to find as many different combinations of presents that can be bought for up to £10. The key here is that the whole £10 does not have to be spent.

So 3 sets of beads and a box of chocolates is one possibility, costing £9 in total.

As usual, look for well a well organised logical approach.

This page can be found in the year 4 Using and Applying maths category.

Christmas presents

More Christmas themed worksheets can be found at;

http://pages.urbrainy.com/happy-christmas-2011