National 5 Maths · SQA past paper

2019 Paper 1

Non-Calculator · 15 questions
1

Question 1

Function notation
2 Marks
2019 P1 Q1

Given that f(x)=5x3\displaystyle f(x)=5x^{3}, evaluate f(2).\displaystyle f(-2).

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-40
2

Question 2

Fractions and mixed numbers
2 Marks
2019 P1 Q2

Evaluate 38×157.\displaystyle \frac{3}{8} \times 1\frac{5}{7}.
Give your answer in its simplest form.

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914\displaystyle \frac{9}{14}
3

Question 3

Expanding brackets
3 Marks
2019 P1 Q3

Expand and simplify (x+5)(2x27x3).\displaystyle (x+5)(2x^{2}-7x-3).

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2x3+3x238x15\displaystyle 2x^{3}+3x^{2}-38x-15
4

Question 4

Arc length
3 Marks
2019 P1 Q4

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

Sector of a circle with angle 240 degrees and radius 30cm

The radius of the circle is 30 centimetres.
Calculate the length of the major arc AB.
Take π=314.\displaystyle \pi=3\cdot14.

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125.6 cm
5

Question 5

Median/Quartiles/Interquartile RangeComparing Calculated Statistics
(3, 2)5 Marks
2019 P1 Q5

The midday temperatures in Grantford were recorded over a nine day period.
The temperatures, in °C, were
4  7  4  3  6  10  9  5  3

(a)  Calculate the median and semi-interquartile range for these temperatures.

Over the same nine day period the midday temperatures in Endoch were also recorded.
The median temperature was 8 °C, and the semi-interquartile range was 1.5 °C.

(b)  Make two valid comments comparing the midday temperatures of Grantford and Endoch during this period.

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(a) Median = 5, SIQR = 2.25
(b) On average Endoch was warmer. Temperatures in Endoch were more consistent.
6

Question 6

Scatter GraphStraight Line Equation
(3, 1)4 Marks
2019 P1 Q6

The fuel consumption of a group of cars is recorded.
The scattergraph shows the relationship between the fuel consumption, F\displaystyle F kilometres per litre, and the engine size, E\displaystyle E litres, of the cars.

Scattergraph showing fuel consumption vs engine size

A line of best fit has been drawn.

(a)  Find the equation of the line of best fit in terms of F\displaystyle F and E.\displaystyle E. Give the equation in its simplest form.

Amaar’s car has an engine size of 1.1 litres.
(b)  Use your equation from part (a) to estimate how many kilometres per litre he should expect to get.

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(a) F=3E+18.5\displaystyle F=-3E+18.5, (b) 15.2
7

Question 7

Changing the subject of a formula
3 Marks
2019 P1 Q7

The area of a trapezium is given by the formula
A=12h(x+y).\displaystyle A=\frac{1}{2}h(x+y).
Make x\displaystyle x the subject of the formula.

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x=2Ahy\displaystyle x=\frac{2A}{h}-y
8

Question 8

Simultaneous equations
(1, 1, 4)6 Marks
2019 P1 Q8

John bought 7 bags of cement and 3 bags of gravel.
The total weight of these bags was 215 kilograms.
(a)  Write down an equation to illustrate this information.

Shona bought 5 bags of cement and 4 bags of gravel.
The total weight of her bags was 200 kilograms.
(b)  Write down an equation to illustrate this information.

(c)  Calculate the weight of one bag of cement and the weight of one bag of gravel.

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(a) 7c+3g=215\displaystyle 7c+3g=215, (b) 5c+4g=200\displaystyle 5c+4g=200, (c) Cement 20 kg, Gravel 25 kg
9

Question 9

Turning Points and Axis of SymmetryParabola Equation from Graph
(1, 1, 1)3 Marks
2019 P1 Q9

The graph shows a parabola.

Parabola with turning point (4,20)

The maximum turning point has coordinates (4, 20) as shown in the diagram.

(a)  Write down the equation of the axis of symmetry of the graph.

The equation of the parabola is of the form y=b(x+a)2.\displaystyle y=b-(x+a)^{2}.
(b)  State the values of (i) a\displaystyle a and (ii) b.\displaystyle b.

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(a) x=4\displaystyle x=4
(b) (i) a=4\displaystyle a=-4, (ii) b=20\displaystyle b=20
10

Question 10

Vector pathwaysAdding and Subtracting vector components
(1, 2)3 Marks
2019 P1 Q10

In triangle PQR, PR=(64)\displaystyle \overrightarrow{PR}=\begin{pmatrix}6\\ -4\end{pmatrix} and RQ=(18).\displaystyle \overrightarrow{RQ}=\begin{pmatrix}-1\\ 8\end{pmatrix}.

Triangle PQR vector diagram

(a)  Express PQ\displaystyle \overrightarrow{PQ} in component form.

M is the midpoint of PR.
(b)  Express MQ\displaystyle \overrightarrow{MQ} in component form.

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(a) (54)\displaystyle \begin{pmatrix}5\\ 4\end{pmatrix}, (b) (26)\displaystyle \begin{pmatrix}2\\ 6\end{pmatrix}
11

Question 11

Angles in regular polygonsAngles in diagrams involving circles
3 Marks
2019 P1 Q11

Pam is designing a company logo.
She starts by drawing a regular pentagon ABCDE.
The vertices of the pentagon lie on the circumference of a circle with centre O.

Regular pentagon in a circle

She then adds to the design as shown in the diagram below.

Pentagon with diameter AF added

AF is a diameter of the circle.
Calculate the size of angle OFB.

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36°
12

Question 12

Rationalising the denominator
3 Marks
2019 P1 Q12

Express 240\displaystyle \frac{\sqrt{2}}{\sqrt{40}} as a fraction with a rational denominator.
Give your answer in its simplest form.

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510\displaystyle \frac{\sqrt{5}}{10}
13

Question 13

Identify equation of trigonometric graph
2 Marks
2019 P1 Q13

Part of the graph of y=3cos(x+45)\displaystyle y=3\cos(x+45)^{\circ} is shown in the diagram.

Graph of y=3cos(x+45)

The graph has a minimum turning point at A.
State the coordinates of A.

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(135, -3)
14

Question 14

Linear equations and inequations
3 Marks
2019 P1 Q14

Solve the equation x21=3x5.\displaystyle \frac{x}{2}-1=\frac{3-x}{5}.

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x=167\displaystyle x=\frac{16}{7}
15

Question 15

Quadratic equation by factorising
(1, 4)5 Marks
2019 P1 Q15

A ball is kicked from a clifftop.

Ball kicked from cliff

The height, h\displaystyle h metres, of the ball relative to the clifftop after t\displaystyle t seconds is given by h=12t5t2.\displaystyle h=12t-5t^{2}.
(a)  Calculate the height of the ball above the clifftop after 2 seconds.

The graph below represents the height, h\displaystyle h metres, of the ball relative to the clifftop after t\displaystyle t seconds.

Graph of ball height

The sea is 17 metres below the clifftop.
(b)  After how many seconds will the ball hit the sea?

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(a) 4 metres, (b) 3.4 seconds