Name _____________________________________ Date ______________________
SATS LEVEL 5:
“Explain your answer”
Julie says,
‘I added three odd numbers
and my answer was 50’
Explain why Julie cannot be correct.
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1 mark
An explanation which recognises that the sum of adding three odd numbers is always odd, eg
 ‘Because odd + odd + odd = odd’;
 ‘Because three odd numbers can’t add up to an even number’;
 ‘Because an odd number of odd numbers makes an odd number’.
Do not accept numerical exemplification without further explanation, eg
 ‘Because 21 + 23 + 7 = 51’;
 ‘Because 21 + 23 + 6 = 50’.
Do not accept vague or arbitrary explanations, eg
 ‘Because 50 is even’;
 ‘Because you can only do it with two odd numbers
Kim knows that
137  28 = 3836
Explain how she can use this information to work out this multiplication.
138  28
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1 mark
Explanation that implies that 28 must be added to 3836, eg:
 ‘Just add another 28 on’
 ‘Do another 28 on’
 ‘It’s an extra 28’
 ‘3836 + 28’
Do not accept vague or arbitrary reasons, eg:
‘Do the same sum but add 1 to the number’;
‘Do a times sum’;
‘Just another unit on’.
No mark is awarded for giving the answer 3864 without an adequate
explanation.
Leila knows that
65 × 3 = 195
Explain how she can use this information to find the answer to this multiplication:
165 × 3
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1 mark
Explanation which indicates that 300 can be added to 195, eg
1
 ‘It’s 3 × 100 more’;
 ‘You add another 300 on’;
 ‘3 × 65 = 195, 3 × 100 = 300 so it’s 495’;
 ‘100 has been added to 65, so multiply 100 by 3 and add it to 195’.
An answer to the multiplication is not required and no mark is awarded for it.
Do not accept vague answers such as:
 ‘You work it out’;
 ‘Do a sum’;
 ‘It’s nearly the same except it has 100 in front of it’.
The rule for this sequence of numbers is ‘add 3 each time’.
1
4
7
10
13
16
…
The sequence continues in the same way.
Mary says,
‘No matter how far you go there will never be a
multiple of 3 in the sequence’ .
Is she correct?
Circle Yes or No.
Yes / No
Explain how you know.
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1 mark
Explanation which recognises that each number is one more than a multiple of 3,eg
 ‘It starts at 1 and keeps adding 3 so it misses all the multiples of 3’,
 ‘Multiples of 3 are all 1 less than the numbers’.
No mark is awarded for circling ‘Yes’ alone.
Do not accept vague or arbitrary explanations such as
 ‘They’re too big’;
 ‘It doesn’t go far enough’;
 ‘It is adding 3 all the time’.
If ‘No’ is circled but a correct unambiguous explanation is given then award the mark.
This chart shows the amount of money spent in a toy shop in three months.
October
November
December
0
£10 000
£20 000
£30 000
How much more money was spent in the shop in December than in November?
£
1 mark
Stepan says,
‘In November there was a 100% increase
on the money spent in October’.
Is he correct?
Yes / No
Circle Yes or No.
Explain how you can tell from the chart.
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1 mark
(a)
£17 500
1m
Accept 17500 with or without commas or spaces.
(b)
An explanation which recognises
1m
that November sales were double October, eg
 ‘October was 7500 and November was 7500 more which is 100%’;
 ‘November is twice October, which is 200%’.
No mark is awarded for circling ‘Yes’ alone.
Do not accept vague or arbitrary answers, eg
 ‘November is more than October’;
 ‘Because November is £15000’.
If ‘No’ is circled but a correct unambiguous explanation is given then award the mark.
Which is larger,
1
2
or ?
3
5
Explain how you know.
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1 mark
An appropriate explanation which recognises that:
1 5
2 6

and 
3 15
5 15
No mark is awarded for writing
2
alone.
5
OR
1 2
2
 which is less than
3 6
5
Do not accept vague or arbitrary explanations, eg
2
1
 ‘Because is bigger than ‘;
5
3
1
 ‘Because comes first on a number line’.
3
OR
that
1
2
2
is less than
because 3 × is greater than 1
3
5
5
90p
75p
6 green apples for 75p
10 red apples for 90p
Jason bought some bags of green apples and some bags of red apples. He spent £4.20
How many bags of each type of apples did he buy?
Show
your working.
You may get
a mark.
bags of
green apples
bags of
red apples
2 marks
Nika and Hassan bought some bags of apples. Nika says,
‘I bought more apples than Hassan, but I spent
less money.’
Explain how this is possible.
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1 mark
(a)
Award TWO marks for correct answer as shown:
2
bags of
green apples
bags of
red apples
Both numbers must be correct for the award of the marks.
3
If the answer is incorrect, award ONE mark for evidence of appropriate working, eg Listing of cost of apples
(b)
An explanation that shows how it is possible to buy more apples but spend less money,
 ‘Nika buys 2 bags of red apples, giving 20 apples for £1.80, and Hassan buys 3 bags of green apples,
giving 18 apples for £2.25’.
Do not accept vague or arbitrary explanations, eg
 ‘She got bigger bags than he did’;
 She bought a lot of small ones’.
Ignore slight errors in arithmetic that do not contradict the explanation.
The pie charts show the results of a school’s netball and football matches.
lost
lost
won
won
drawn
drawn
Netball
Football
The netball team played 30 games.
The football team played 24 games.
Estimate the percentage of games that the netball team lost.
%
1 mark
David says,
‘The two teams won the same number of games’.
Is he correct?
Circle Yes or No.
Yes / No
Explain how you know.
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1 mark
(a)
Answer in the range 30% to 36% inclusive.
1m
(b)
An explanation which recognises that both teams won half their games,
1m
but both teams played a different number of games, eg
U1
 Half of 30 is not the same as half of 24;
 Because of 30 e 15 but of 24 = 12;
 Because 15 is more than 12.
No mark is awarded for circling ‘No’ alone.
Do not accept vague or arbitrary explanation, eg
 The netball team played more games;
 Both teams won half their games;
 30 is more than 24’.
If ‘Yes’ is circled but a correct unambiguous explanation is given, then award the mark.