Transcript Board 12 - WordPress.com

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NUMBER
ALGEBRA
F
F
E
D
C
E
D
C
SHAPE
HANDLING
SPACE & M
DATA
F
E
D
C
F
E
D
C
SHAPE and
SPACE
HANDLIN
G DATA
SHAPE and
SPACE
HANDLIN
G DATA
Where would the fraction below go on the
number line?
0
½
1
1
4
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Answer
Where would the fraction below go on the
number line?
0
½
1
4
Back to board
1
What is 15% of £44
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Answer
What is 15% of £44
£6.60
Back to board
Explain?
What is 15% of £44
£6.60
10% = £4.40
+ 5% = £2.20
15 % = £6.60
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What is
Back to board
1
3
+
3
8
Answer
What is
1
3
+
3
8
17
24
Back to board
Explain?
What is
1
3
+
3
8
The lowest common multiple of 3 and
8 is 24. Find equivalent fractions with
this denominator.
8
9
+
24
24
Back to board
17
24
Use your calculator to work out the
calculation shown, giving your answer
correct to 2 significant figures.
(42.72 - 17.62)

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Answer
Use your calculator to work out the
calculation shown, giving your answer
correct to 2 significant figures.
(42.72 - 17.62)
39

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Explain?
Use your calculator to work out the
calculation shown, giving your answer
correct to 2 significant figures.
(42.72 - 17.62)
Calculator display gives

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38.90411289..
39
What are the co-ordinates of each toy?
10
8
6
4
2
0
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2
4
6
8
10
Answer
What are the co-ordinates of each toy?
10
(2,8)
8
(8,7)
6
Remember:
(4,4)
4
2
0
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2
4
6
8
10
then up
across
first
(a) How many balls are in the 6th pattern?
(b) What is the name of this number sequence?
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Answer
(a) How many balls are in the 6th pattern?
(b) What is the name of this number sequence?
(a) 21
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(b) Triangular Numbers
Explain?
(a) How many balls are in the 6th pattern?
(b) What is the name of this number sequence?
1
1+2
(a) 21
1+2+3
1+2+3+4
1+2+3+4+5
(b) Triangular Numbers
1 + 2 + 3 + 4 + 5 + 6 = 21
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Solve :
2(x - 6) = x + 7
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Answer
Solve :
2(x - 6) = x + 7
x = 19
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Explain?
Solve :
2(x - 6) = x + 7
2x - 12 = x + 7 (expanding brackets)
x - 12 = 7 (subtracting x from both sides)
x = 19 (Adding 12 to both sides)
Check: is 2(19 - 6) = 19 + 7 ? 
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x = 19
What is the algebraic rule in (terms of n)
for the number of wooden strips in the nth
diagram?
1
3
2
n
?
4
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7
10
Answer
What is the algebraic rule in (terms of n)
for the number of wooden strips in the nth
diagram?
1
3
2
n
?
4
10
7
nth term: tn= 3n + 1
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Explain?
What is the algebraic rule in (terms of n)
for the number of wooden strips in the nth
diagram?
1
3
2
n
?
4
7
10
nth term: tn= 3n + 1
Three times the diagram number + 1
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Snoopy said that all the shapes below have
the same area (6 cm2) so they must have
the same perimeter as well. Hippo
disagreed. Who was right?
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Answer
Snoopy said that all the shapes below have
the same area (6 cm2) so they must have
the same perimeter as well. Hippo
Hippo
disagreed. Who was right?
Back to board
Explain?
Snoopy said that all the shapes below have
the same area (6 cm2) so they must have
the same perimeter as well. Hippo
Hippo
disagreed. Who was right?
14 cm
10 cm
14 cm
12 cm
Remember that the perimeter is the distance
all the way around the outside of a shape.
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What is the approximate weight of the
bag of sugar in imperial units?
Sugar
2 kg
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Answer
What is the approximate weight of the
bag of sugar in imperial units?
Sugar
4 lbs
2 kg
1 kg  2.2 lbs
2 kg  4.4 lbs
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Find (giving a reason) angle p.
45o
p
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Answer
Find (giving a reason) angle p.
45o
p
Angle p = 450 (Corresponding angles are equal)
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Find the volume of the triangular
based prism.
Not to
scale
7 cm
6 cm
8 cm
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Answer
Find the volume of the triangular
based prism.
Not to
scale
7 cm
6 cm
8 cm
168 cm3
Back to board
Explain?
Find the volume of the triangular
Remember:
based prism.
V = base x height x length
2
Not to
scale
7 cm
6 cm
8 cm
168 cm3
Back to board
8x7
x6
V=
2
= 28 x 6 = 168
The frequency diagram below shows the scores
for some students in a maths test.
How many students scored less than 20 marks?
25
Test Scores
Frequency
20
15
10
5
0-9
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10-19 20-29 30-39 40-49 50-60
Marks
Answer
The frequency diagram below shows the scores
for some students in a maths test.
How many students scored less than 20 marks?
25
Test Scores
Frequency
20
15
10
22
5
0-9
Back to board
10-19 20-29 30-39 40-49 50-60
Marks
Explain?
The frequency diagram below shows the scores
for some students in a maths test.
How many students scored less than 20 marks?
25
Test Scores
Frequency
20
15
15
10
7
22
5
0-9
Back to board
10-19 20-29 30-39 40-49 50-60
Marks
One counter is drawn from the bag at random.
Where would you mark the probability of it
being red on the probability line?
0
Back to board
½
1
Answer
One counter is drawn from the bag at random.
Where would you mark the probability of it
being red on the probability line?
0
½
1/2
P(red) =6/12 = 1/2
6 of the counters are red out of
a total of 12 counters.
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1
80 people were asked which one of three TV
Channels they preferred to watch. Complete
the partially filled two-way table below.
BBC 1
Male
16
Female
10
Total
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ITV
CH 4
Total
9
30
20
80
Answer
80 people were asked which one of three TV
Channels they preferred to watch. Complete
the partially filled two-way table below.
BBC 1
ITV
CH 4
Total
Male
16
5
9
30
Female
10
20
20
50
Total
26
25
29
80
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Ice Creams Sold
The scatter graph with line of best fit shows information on
ice cream sales over a period of 10 days last summer.
500
450
400
(a) Describe the type
350
of correlation shown.
300
250
200
150
100
0
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1
(b) Use the line of
best fit to estimate the
number of ice creams
sold on a day when
there is 3 hours of
sunshine.
2 3 4 5 6 7 8 9 10
Hours of Sunshine
Answer
Ice Creams Sold
The scatter graph with line of best fit shows information on
ice cream sales over a period of 10 days last summer.
500
450
400
(a) Describe the type
350
of correlation shown.
300
250
200
150
100
0
1
(b) Use the line of
best fit to estimate the
number of ice creams
sold on a day when
there is 3 hours of
sunshine.
2 3 4 5 6 7 8 9 10
Hours of Sunshine
(a) positive
(b)  205
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Explain?
Ice Creams Sold
The scatter graph with line of best fit shows information on
ice cream sales over a period of 10 days last summer.
500
450
400
(a) Describe the type
350
of correlation shown.
300
250
200
150
100
0
1
(b) Use the line of
best fit to estimate the
number of ice creams
sold on a day when
there is 3 hours of
sunshine.
2 3 4 5 6 7 8 9 10
Hours of Sunshine
(a) As one quantity increases
so does the other.
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(a) positive
(b)  205