Mathematics GCSE Higher Tier 2011 1380

Mathematics GCSE Higher Tier 2011
1380 Taster Pages
Question 7 (June 2011 – 1380/3H)
a)
b) this is a vector translation as the shape P is simply picked and moved so many places horizontally
and so many places vertically. It doesn’t turn or change size.
It has moved 6 places to the left (-6) and 1 place down (-1)
Vector translation www.chattertontuition.co.uk 0775 950 1629
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Mathematics GCSE Higher Tier 2011
1380 Taster Pages
Question 18 (June 2011 – 1380/3H)
a) the modal class interval is the one with the highest frequency
modal class interval is 90 m 100
b)
Time (m minutes)
70 m 80
70 m 90
70 m 100
70 m 110
70 m 120
70 m 130
Cumulative Frequency
4
16
50
82
108
120
Check that the final cumulative frequency is the same as the total frequency – which it is.
c)
To find the median draw a horizontal line across from a cumulative frequency of 60 to meet the
curve. Where this line meets the curve drop it down to meet the time axis. This will be the median.
Median = 103 minutes
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Mathematics GCSE Higher Tier 2011
1380 Taster Pages
Question 19 (June 2011 – 1380/3H)
4x + y = 10 equation 1
2x – 3y = 19 equation 2
We can solve by elimination or by substitution
Elimination method
We need to have either the same number of x or the same number of y
Multiply equation 1 by 3 so that we end up with 3y
12x + 3y = 30 equation 3
2x – 3y = 19 equation 2 (unchanged)
Add the two equations together to make the y terms disappear
14x = 49
Divide both sides by 14
x = = = 3.5
Now we have x we can put this back into equation 1 to get y
(4 x 3.5) + y = 10
14 + y = 10
Subtract 14 from both sides
y = -4
x = 3.5, y = -4
Now check the answers by putting both back into equation 2
(2 x 3.5) – (3 x -4) = 7 - -12 = 7 + 12 = 19
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Mathematics GCSE Higher Tier 2011
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Substitution Method
We can easily rearrange equation 1 to get y as the subject
y = 10 – 4x
Now substitute this into the second equation replacing the y with 10 – 4x
2x – (3 x (10 – 4x)) = 19
2x – (30 – 12x) = 19
2x – 30 + 12x = 19
Grouping terms
14x – 30 = 19
Add 30 to both sides
14x = 49
Divide both sides by 14
x = = = 3.5
Now we have x we can put this back into the rearranged equation 1 to get y
Y = 10 - (4 x 3.5)
Y = 10 - 14
y = -4
x = 3.5, y = -4
Now check the answers by putting both back into equation 2
(2 x 3.5) – (3 x -4) = 7 - -12 = 7 + 12 = 19
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Mathematics GCSE Higher Tier 2011
1380 Taster Pages
Question 3 (June 2011 – 1380/4H)
a)
45
15
3
5
3
so 45 = 3 x 3 x 5 = 32 x 5
b) we can do the same to 30
30
10
3
5
23
30 = 2 x 3 x 5
45 = 3 x 3 x 5
Common factors are 3 and 5
3 x 5 = 15
HCF = 15
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Mathematics GCSE Higher Tier 2011
1380 Taster Pages
Question 24 (June 2011 – 1380/4H)
1st pen
2nd pen
4
9
red
3
9
red
5
10
2
9
3
10
green
5
9
blue
green
5
9
green
red
2
9
blue
2
9
2
10
blue
red
3
9
1
9
blue
green
Note that Gary is not replacing the first pen so the probabilities change for the second pen
Prob (red, red) = x = (normally I would cancel down at this stage but we are going to have to
add other fractions so best not to simplify yet)
Prob (blue, blue) = x = Prob (green, green) =
x =
Prob (same colour) = + + = = www.chattertontuition.co.uk 0775 950 1629
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Mathematics GCSE Higher Tier 2011
1380 Taster Pages
If you like these worked answers then why not purchase the complete set of answers for these
question papers by visiting www.chattertontuition.co.uk/GCSE-maths-Edexcel-2011
It should be noted that Chatterton Tuition is responsible for these solutions. The solutions have not
been produced nor approved by Edexcel. In addition these solutions may not necessarily constitute
the only possible solutions.
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