National 5 Maths · SQA past paper

2018 Paper 2

Calculator · 18 questions
1

Question 1

Appreciation and Depreciation
3 Marks
2018 P2 Q1

Households in a city produced a total of 125 000 tonnes of waste in 2017.
The total amount of waste is expected to fall by 2% each year.
Calculate the total amount of waste these households are expected to produce in 2020.

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117 649 tonnes
2

Question 2

Arc length
3 Marks
2018 P2 Q2

The diagram below shows a sector of a circle, centre C.

Sector of a circle with angle 320 degrees

The radius of the circle is 7.4 centimetres.
Angle ACB is 320\displaystyle 320^{\circ}.
Calculate the length of the major arc AB.

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41.3 cm
3

Question 3

Magnitude
2 Marks
2018 P2 Q3

Find r\displaystyle |\mathbf{r}|, the magnitude of vector r=(24128)\displaystyle \mathbf{r}=\begin{pmatrix}24\\ -12\\ 8\end{pmatrix}.

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28
4

Question 4

Linear equations and inequations
3 Marks
2018 P2 Q4

Solve, algebraically, the inequation 3x<6(x1)12.\displaystyle 3x<6(x-1)-12.

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x>6\displaystyle x>6
5

Question 5

Standard DeviationComparing Calculated Statistics
(4, 2)6 Marks
2018 P2 Q5

A farmers' market took place one weekend. Stallholders were asked to record the number of customers who visited their stall.
The number of customers who visited six of the stalls on Saturday were as follows:
120, 126, 125, 131, 130, 124.
(a)  Calculate the mean and standard deviation of the number of customers.

The mean number of customers who visited these six stalls on Sunday was 117 and the standard deviation was 6.2.
(b)  Make two valid comments comparing the number of customers who visited these stalls on Saturday and Sunday.

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(a) Mean = 126, Standard Deviation = 4.05
(b) On average the number of customers was higher on Saturday. The number of customers was less varied (more consistent) on Saturday.
6

Question 6

Function notation
2 Marks
2018 P2 Q6

A function is defined as f(x)=5+4x\displaystyle f(x)=5+4x.
Given that f(a)=73\displaystyle f(a)=73, calculate a.\displaystyle a.

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a=17\displaystyle a=17
7

Question 7

Volume - simple shape
3 Marks
2018 P2 Q7

A toy company makes juggling balls in the shape of a sphere with a diameter of 6.4 centimetres.

Sphere with diameter 6.4 cm

Calculate the volume of one juggling ball.
Give your answer correct to 2 significant figures.

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140 cm³
8

Question 8

Trigonometric equation
3 Marks
2018 P2 Q8

Solve the equation 7sinx+2=3\displaystyle 7\sin x^{\circ}+2=3, for 0x<360.\displaystyle 0\le x < 360.

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x=8.2,171.8\displaystyle x=8.2, 171.8
9

Question 9

Sine rule: calculate length
3 Marks
2018 P2 Q9

In this diagram:
•  angle ABD = 75\displaystyle 75^{\circ}
•  angle BDC = 37\displaystyle 37^{\circ}
•  BC = 20 centimetres.

Triangle diagram

Calculate the length of DC.

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32.1 cm
10

Question 10

Vector pathways
2 Marks
2018 P2 Q10

In the diagram below, AB\displaystyle \overrightarrow{AB} and EA\displaystyle \overrightarrow{EA} represent the vectors u\displaystyle \mathbf{u} and w\displaystyle \mathbf{w} respectively.

Vector diagram

ED=2AB\displaystyle \bullet \quad \overrightarrow{ED}=2\overrightarrow{AB}
EA=2DC\displaystyle \bullet \quad \overrightarrow{EA}=2\overrightarrow{DC}
Express BC\displaystyle \overrightarrow{BC} in terms of u\displaystyle \mathbf{u} and w\displaystyle \mathbf{w}.
Give your answer in its simplest form.

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u12w\displaystyle \mathbf{u}-\frac{1}{2}\mathbf{w}
11

Question 11

Reversing a percentage changeScientific notation
3 Marks
2018 P2 Q11

Venus and Earth are two planets within our solar system.

Venus and Earth

The volume of Venus is approximately 93×1011\displaystyle 9\cdot3\times10^{11} cubic kilometres.
This is 85% of the volume of Earth.
Calculate the volume of Earth.

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1.1×1012\displaystyle 1.1 \times 10^{12} km³
12

Question 12

Pythagoras in circle diagrams
4 Marks
2018 P2 Q12

The shape below is part of a circle, centre O.

Part of a circle

The circle has radius 13 centimetres.
AB is a chord of length 20 centimetres.
Calculate the width of the shape.

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21.3 cm
13

Question 13

Cosine rule: calculate angleBearings in Trigonometry questions
4 Marks
2018 P2 Q13

A ferry and a trawler receive a request for help from a stranded yacht.
On the diagram the points F, T and Y show the positions of the ferry, the trawler and the yacht respectively.

Bearings diagram

• FY is 7.2 kilometres.
• TY is 5.6 kilometres.
• FT is 10.3 kilometres.
• F is on a bearing of 240\displaystyle 240^{\circ} from T.
Calculate the bearing of the yacht from the trawler.

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282\displaystyle 282^{\circ}
14

Question 14

Coordinate Geometry with straight line equationStraight Line Equation
2 Marks
2018 P2 Q14

A straight line has equation 2x5y=20.\displaystyle 2x-5y=20.
Find the coordinates of the point where this line crosses the y-axis.

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(0, -4)
15

Question 15

Multiply or divide Algebraic Fractions
3 Marks
2018 P2 Q15

Express nn24÷3n2\displaystyle \frac{n}{n^{2}-4}\div\frac{3}{n-2}, n2,n2\displaystyle n\ne-2, n\ne2 as a single fraction in its simplest form.

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n3(n+2)\displaystyle \frac{n}{3(n+2)}
16

Question 16

Pythagoras in 3d
4 Marks
2018 P2 Q16

Chris wants to store his umbrella in a locker.
The locker is a cuboid with internal dimensions of length 40 centimetres, breadth 40 centimetres and height 70 centimetres.

Locker diagram

The umbrella is 85 cm long.
He thinks it will fit into the locker from corner P to corner M.
Is he correct? Justify your answer.

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Yes, since 85 < 90
17

Question 17

Area of a TriangleSector area
5 Marks
2018 P2 Q17

In the diagram below AOD is a sector of a circle, with centre O, and BOC is a triangle.

Diagram of sector and triangle

In sector AOD:
• radius = 30 centimetres
• angle AOD = 75.\displaystyle 75^{\circ}.
In triangle OBC:
• OB = 38 centimetres
• OC = 55 centimetres.
Calculate the area of the shaded region, ABCD.

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420 cm²
18

Question 18

Similar areas/volumes
(3, 2)5 Marks
2018 P2 Q18

A cinema sells popcorn in two different sized cartons.

Popcorn cartons

The small carton is 16 cm deep and has a volume of 576 cubic centimetres.
The large carton is 24 cm deep and has a volume of 1125 cubic centimetres.
(a)  Show that the two cartons are not mathematically similar.
(b)  The large carton is redesigned so that the two cartons are now mathematically similar. The volume of the redesigned large carton is 1500 cubic centimetres. Calculate the depth of the redesigned large carton.

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(a) Scale factors do not match
(b) 22 cm