a selection of maths problems for year 4
TRANSCRIPT
© AWE 2012 www.spearmaths.co.uk
D18
Objectives
Use drawings or resources to help visualise the problem
Use a systematic approach to solve the problem
Choose and use an appropriate method of recording
Try other possibilities to test the solution
Polygon Hunt
On a 3 x 3 pinboard, how many different triangles can you make?
Different means no ‘flip overs’ or ‘turn rounds’
How many different quadrilaterals can you make on a 3 x 3
pinboard? What about pentagons? Hexagons? Heptagons?
Can you make an octagon on a 3 x 3 pinboard?
These triangles
are all the same
These triangles
are different
© AWE 2012 www.spearmaths.co.uk
Answer to D18 Polygon Hunt
These are the 8 triangles you can make.
You can make:
8 different triangles
16 different quadrilaterals
23 different pentagons
22 different hexagons
5 different heptagons
It is impossible to make an octagon on a 3x3 pinboard
© AWE 2012 www.spearmaths.co.uk
K x A = DF
F x A = BD
D x A = H
E x A = BE
J x A = DG
H x A = BK
B x A = A
G x A = DB
BC x A = AC
BD x A = AH
BB x A = AA
A x A = J
L28
Objectives Recognise simple patterns or relationships, generalise and predict
Suggest extensions by asking ‘what if…?’ or ‘what could I try next?’ Look for any relationships and patterns in the information given Use recording to make sense of the information given and to find
missing information
Check that the answer meets all of the criteria
K x A
Each letter (in the equations
on the left of the page)
stands for a single digit.
Where there are two letters
next to each other, this
stands for a two-digit number.
Each letter stands for the
same digit throughout all the
equations.
Can you work out what digit
each letter stands for?
Hint: You don’t have to start
at the top!
© AWE 2012 www.spearmaths.co.uk
Answer to L28 K x A
A=3
B=1
C=0
D=2
E=5
F=4
G=7
H=6
J=9
K=8
NB: There is no ‘I’ in the list as this may look too much like a ‘1’
© AWE 2012 www.spearmaths.co.uk
P100
Objectives Recognise patterns or relationships
Generalise and predict Suggest extensions by asking ‘what if…?’ or ‘what could I try next?’ Organise the recording of possibilities eg in an ordered list or table
Have a system for finding the possibilities eg start with the smallest number, know when all possibilities are found, check for repeats of possibilities
Sheep and Chickens +
Simon looked at the sheep and chickens in a field.
He counted 28 legs.
How many sheep and chickens could there be?
Find as many ways to do it as you can.
Show your thinking.
© AWE 2012 www.spearmaths.co.uk
Answer to P100 Sheep and Chickens +
0 + 28 0 sheep, 14 chickens: doesn’t really count as it doesn’t include any sheep
4 + 24 1 sheep, 12 chickens
8 + 20 2 sheep, 10 chickens
12 + 16 3 sheep, 8 chickens
16 + 12 4 sheep, 6 chickens
20 + 8 5 sheep, 4 chickens
24 + 4 6 sheep, 2 chickens
28 + 0 7 sheep, 0 chickens: doesn’t really count as it doesn’t include any chickens
© AWE 2012 www.spearmaths.co.uk
R23
Objectives
Recognise and explain patterns or relationships, generalise and
predict
Describe and extend simple number sequences
Use a systematic approach to solve the problem
Choose and use an appropriate method of recording
3 Consecutive Numbers
Consecutive numbers are whole numbers that follow each other
without gaps: 1, 2 and 3 are consecutive; 2, 3 and 7 aren’t.
Find three consecutive numbers that add up to 39
What other numbers up to 50 can you make by adding three
consecutive numbers?
Look for a pattern.
What is the pattern of numbers you can make by adding four
consecutive numbers?
© AWE 2012 www.spearmaths.co.uk
Answer to R23 3 Consecutive Numbers
1 + 2 + 3 = 6
2 + 3 + 4 = 9
3 + 4 + 5 = 12
4 + 5 + 6 = 15
5 + 6 + 7 = 16 etc.
The sum of three consecutive numbers = 3 x the ‘middle’ number, so all the answers are
in the 3 x table (ie 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48)
12 + 13 +14 =39
4 Consecutive numbers:
1 + 2 + 3 + 4 = 10
2 + 3 + 4 + 5 = 14
3 + 4 + 5 + 6 = 18 and so on going up in 4s
© AWE 2012 www.spearmaths.co.uk
W22
Objectives
Choose and use appropriate number operations and appropriate
ways of calculating to solve problems
Use a systematic approach to solve the problem
Use all four operations to solve word problems involving
numbers in ‘real life’
1, 2, 3 and 4 make…
Use only the digits 1, 2, 3, and 4 (one of each).
You can also use any operations you like: + - x ÷ as many
times as you like
Here is a calculation that totals 1: 2 + 3 – 4 x 1 = 1
Here is a calculation that totals 40: 43 – 2 – 1 = 40
Now make up calculations that total 2, 3, 4, 5, 6, 7 etc.
Can you make each number
from 1 to 40?
Create a way to work systematically.