Upload
jillian-nemo
View
216
Download
1
Embed Size (px)
Citation preview
Primary Schools’ Mathematics Challenge 2008
Final Round QuestionsHere is a selection of questions asked over two
rounds.
To access answers left click mouse and an automated sequence will appear.
The questions may very slightly from those presented and are not in the order they were asked.
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
The sum of three consecutive numbers is 15.
What is their product?
Clue: 97, 98, 99, 100 and 101 are consecutive numbers.
The consecutive numbers are 4 5 6
Their product is 4 x 5 x 6 =
20 x 6 = 120
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
The top number is the product of the two numbers below
The bottom number is the difference between the two numbers above
Which numbers could be missing from the grid below?
94
455 9
4
11713
Two possible answers
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
An oval dog racing track is 240 metres all round.
Jack the Flash wins a three lap race in a time of 1 min. 30 seconds.
How many metres does the dog run on average per second?
The dog travels 720 metres (3 x 240m) in 90 seconds
Divide 720m by 90.
720m ÷ 90 = 8m per second on average
Quick isn’t he?
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
2 + 6 10 - 8 2 x 5+ 9 ÷ 3
+ 15 - 9
+
A
The grid is completed by adding together the boxes as shown by the arrows.
Which number fits into box A?
6 X 5 +
40 19+
2 3
610
8
30
10
13
59
40 19
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Which five numbers are missing from this number track?
25 x3 Minus 19 Divide by 8
Multiply by 7Add 1
75 56
50 49 7
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
The rule for this sequence is find a quarter and add 11.
Write in the two missing numbers in the sequence below.
4 12 14 14.5
¼ of 12 is 3. 3 + 11 make 14
¼ of 14 is 3.5 3.5 + 11 make 14.5
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
The rectangle has the same perimeter as the square.
What is the length of the shorter side of the rectangle?
Square Area
81cm2
10.75 cm
The length of one side is 9cm
The perimeter is 36cm (9cm x 4)
The perimeter is 36cm
Two of the sides total 21.5 cm (10.75 x 2)
The other two sides total 36 - 21.5 = 14.5 cm
The short side is 14.5cm ÷ 2
The short side is 7.25cm
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Tom finds the denominator of a fraction by calculating three-fifths of 25.
He finds the numerator by finding a quarter of a half of 16
What is Tom’s fraction?
15
2
2
15
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Here are six number cards.
The 12 card must be used in each fraction.
16 3 12 4 8 9
Use the cards to make two different fractions equivalent to ¾
12
12
16
9
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
What fraction of the large square is not shaded grey?
The denominator is 16.
10 squares are not grey
The fraction not shaded is 10/16 or 5/8
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Add 0.25 to each of the decimal fractions below.
0.35 0.050.15 0.5 0.55
Rewrite the new decimal fractions in order starting with the largest.
0.35 0.050.15 0.5 0.55
Add 0.25 to each decimal
0.6 0.30.4 0.75 0.8
Rewrite starting with the largest decimal
0.8 0.75 0.6 0.4 0.3
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
This diagram is placed in the middle of a square grid.
The new grid is the same height as the diagram shown
What percentage of the new large square grid is red?
Because the diagram is five squares high the new big square
is made up of 25 smaller squares.
The diagram fits in the middle.
Three out of the 25 squaresare red.
As a percentage this is 12 out of 100 or 12%
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Which mathematics terms are hidden in these anagrams?
ALL PALER
MYSTERY M
ALL CUT ACE
Then find your answers on the word search grid.
U PA T E A L Y
N AA A S F E T
E R`S P A A L E
L AC U L T E N
A LC T Y S Y M
S EY M M T R Y
T LC M E I N K
S LY M E Z X P
P
A
R
A
L
L
E
L
S
Y
M
C
E
T
Y
R
PARALLEL
SYMMETRY
CALCULATE
P
A
R
A
L
L
E
L
S EY M M T R Y
L AC U L T EAC
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
A
T U RQLIE
RLNUEGESQ
Three mathematical words are mixed up in this circle of letters.
Each word must contain the centre letter A once only
U R
E
SQ
U R ES Q AE
Q
U
E
L
Q
U
E LQ UE
T
LI
RNEG
T LIR N EG
A
A
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
You have a zero to ninety-nine hundred square.
A. How many times does the 9 digit appear?
B. Which digit appears the least number of times?
0 1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19
20 21 22 23 24 25 26 27 28 29
30 31 32 33 34 35 36 37 38 39
40 41 42 43 44 45 46 47 48 49
50 51 52 53 54 55 56 57 58 59
60 61 62 63 64 65 66 67 68 69
70 71 72 73 74 75 76 77 78 79
80 81 82 83 84 85 86 87 88 89
90 91 92 93 94 95 96 97 98 99
9
19
29
39
49
59
69
79
89
9990 91 92 93 94 95 96 97 98
0
10
20
30
40
50
60
70
80
90
11 times
9 times
10 times
11 + 9 = 20
0 ten times
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
All the triangles in this shape are equilateral.
The perimeter of the large triangle is 108cm.
What is the perimeter of the blue rhombus made by the two equilateral
triangles?
The side of the large triangle is 108cm ÷ 3 = 36cm
One side of the rhombus is 36cm ÷ 2 = 18cm
The perimeter of the rhombus is 18cm x 4 = 72cm
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Use the symbols < > = to make these number sentences correct
A. ( 2 x 19 ) + 15 13 x 4
B. 10 x 10 x 10 40 x 25
C. 9.9 - 3.3 9.3 - 3.9
38 + 15 = 53 52
1000 1000
6.6 5.4
>
=
>
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
A bag of crisps weights 25g
How many bags of crisps are in a box if its contents weigh 2Kg?
2 Kg = 2000 g
2000 g ÷ 25 = 80
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
In a sale a shop makes the following offer:
Buy one item and get a second item at a 20% discount.
The discount applies to the cheaper item bought.
Jack buys a football and a pair of trainers.
How much does he pay altogether?
£25.49
£19.99
£10.50
The football is cheaper so£10.50 ÷ 5 (20%) = £2.10 this is his discount.
He pays £10.50 - £2.10 = £8.40 for the football
For the trainers and the football Jack pays £25.49 + £8.40 = £33.89
20% is the same as one-fifth
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
School starts at 8:50 a.m.
Amy arrives 13 minutes early. Ben is late.
Ben and Amy arrive 35 minutes apart.
What time does Ben arrive at school?
Amy arrives at ( 8:50 - 13min. ) 8:37
Ben arrives at ( 8:37 + 35min. ) 9:12
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
18cm
Jade has three Russian Dolls.
Each doll is 1½ (1.5) times bigger than the previous one.
A B C
How tall are dolls A and C?
Doll A is 12 cm. 18 cm ÷ 1.5 = 12 cm
Doll C is 27 cm. 18 cm x 1.5 = 27 cm
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
A transit van and its parcels weigh 2.25 Tonnes altogether.
The van weighs 1.75 Tonne.
Jack loads the van with 125 similar parcels.
How much does each parcel weigh?
Altogether the parcels weigh
2.25T - 1.75 T = 500 Kg
(2250 Kg - 1750 Kg)
Each parcel weighs
500 Kg ÷ 125 = 4 Kg
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Look at the three separate problems below.
A = 19 + y B = y2 C = (5 x y) - (120 ÷ y)
y = 15, what is the answer to each problem?
A. 19 + 15 = 34
B. 15 X 15 = 225
C. 75 - 8 = 67
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Amy is facing east.
She turns anti-clockwise to face north-west
Through how many degrees does she turn?
E
N
W
N..W.
900450
900 +
450 = 1350
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
A
B
X
800
800
Isosceles triangles A and B are the same size.
What is the value of angle X?
This angle is 1800 - (800 + 800)
= 1800 - 1600 = 200
This angle is also 200 because the triangles are the same size.
Angle X is 1800 - (200 + 200)
= 1800 - 400 = 1400
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
ABC
D
E
Sam is snookered on all the reds.
He plays his shot along the line shown by the white dots.
Which red is he most likely to hit if the ball bounces off the cushion at a right angle?
A
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Art gallery
ENTRY FEE
£1.25 per person
220 people went to the art gallery on Saturday.
How much money is this altogether?
£1.25 X 220 = £275
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Five friends have the weights shown below.
Amy 42 Kg, Ben 51 Kg Jade 46Kg Laura 51Kg Tom 47Kg
What is the difference in Kg between their modal weight and their median weight?
Their modal weight is 51 Kg
Their median weight is 47 Kg
51 Kg - 47 Kg = 4 Kg
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
5 4 = 60 3
15 7 = 7 1
You may use the symbols + - x ÷ once only.
Complete these equations (number sentences)
-
x ÷
+
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Here is part of a multiplication problem solved by using the grid method.
x 30
20
4 20
What is the answer to the calculation when complete?
700 + 140 = 840
5
600 100
120
700
140
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Use the rules to find the next number in each sequence
Find he sum of your three answers
Rule: Add 9 5 14 23
Rule: Multiply by 4 4 16 64
Rule: Subtract 8 120 112 104
256
96
32
32 + 256 + 96 = 384
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Find the total of all the prime numbers between 1 and 20.
Multiply your result by three.
2 3 7 11 13 17 19+ + 5 + + + + +
Total 77
77 x 3 = 231
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
The diagram shows some shapes on a square grid
CA B
D E
a. Which two shapes have the same area as A?
b. Which two shapes have the same perimeter as A?
Shape A has an area of 3 units. Shapes B and E have the same area
Shape A has a perimeter of 4 small units and 2 longer units. Shapes D and E have the same area
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Which of these shapes have at least one line of symmetry?
CA
B D
E
F
A, C, D, F
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
Which of the shapes on the grid have more than 1 line of symmetry?
A B D
C
E F
G
Shapes B D E
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
The shape below is rotated 900 degrees clockwise
Which shape below that shows its new position?
A B C D E F
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
The top line of the rectangle goes through the centre of each of the three similar circles.
The perimeter of the rectangle is 32cm.
What is the radius of each circle?
4 cm
The longer side of the rectangle is 12 cm
The diameter of each circle is 12 cm ÷ 3 = 4cm
The radius of each circle is 4 cm ÷ 2 = 2cm
PRIMARY MATHEMATICS CHALLENGE 2008 - FINAL
x
y
0 2 4 6 8
2
4
6
A. What are the co-ordinates of the centre
of the square?
B. What are the co-ordinates of the
junction of the two straight lines that
make a cross ?
A ( 3, 4 )
B ( 7, 3 )