Home ยป Past Questions ยป Mathematics ยป Waec ยป 2020
1

(a) In the diagram, AB is a tangent to the circle with centre O, and COB is a straight line. If CD//AB and < ABE = 40ยฐ, find: < ODE. 

 (b) ABCD is a parallelogram in which |\(\overline{CD}\)| = 7 cm, I\(\overline{AD}\)I = 5 cm and < ADC= 125ยฐ.

(i) Illustrate the information in a diagram.

(ii) Find, correct to one decimal place, the area of the parallelogram.

(c) If x = \(\frac{1}{2}\)(1 – \(\sqrt{2}\)). Evaluate (2x\(^2\) – 2x).

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2

(a) In the diagram, MNPQ is a circle with centre O, |MN| = |NP| and < OMN =  50ยฐ. Find:

(I) < MNP

(ii) < POQ

 

 (b) Find the equation of the line which has the same gradient as 8y + 4xy = 24 and passes through the point (-8, 12)

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3

The table shows the distribution of marks obtained by students in an examination. 

Marks (%) 0 – 9 10 – 19 20 –  29 30 – 39 40 – 49 50 – 59 60 – 69 70 – 79 80 – 89 90 – 99
Frequency  7 11 17 20 29 34 30 25 21 6

 

(a) Construct a cumulative frequency table for the distribution.

(b) Draw the cumulative frequency curve for the distribution.

(c) Using the curve, find correct to one decimal place, the:

(i) median mark;

(ii) lowest mark for the distinction if 5% of the students passed with distinction

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4

(a)  Two cyclists X and Y leave town Q at the same time. Cyclist X travels at the rate of 5 km/h on a bearing of 049ยฐ and cyclist Y travels at the rate of 9 km/h on a bearing of 319ยฐ.

(a) Illustrate the information on a diagram.

(b) After travelling for two hours, calculate. correct to the nearest whole number, the:

(i) distance between cyclist X and Y;

(ii) bearing of cyclist X from Y.

(c) Find the average speed at which cyclist X will get to Y in 4 hours.

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5

(a) Ms. Maureen spent \(\frac{1}{4}\) of her monthly income at a shopping mall, \(\frac{1}{3}\) at an open market and \(\frac{2}{5}\) of the remaining amount at a Mechanic workshop. If she had N222,000.00 left, find:

(i) her monthly income.

(ii) the amount spent at the open market.

(b) The third term of an Arithmetic Progression (A. P.) is 4m – 2n. If the ninth term of the progression is 2m – 8n. find the common difference in terms of m and n. 

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6

(a) The diagram shows a wooden structure in the form of a cone, mounted on a hemispherical base. The vertical height of the cone is 48 m and the base radius is 14. Calculate, correct to three significant figures, the surface area of the structure, [Take \(\pi = \frac{22}{7}\)]

(b) Five years ago, Musah was twice as old as Sesay. If the sum of their ages is 100, find Sesay’s present age.

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7

(a) Copy and complete the table of values for the relation y = 3 sin 2x. 

x o\(^o\) 15\(^o\) 30\(^o\) 45\(^o\) 60\(^o\) 75\(^o\) 90\(^o\) 105\(^o\) 120\(^o\) 135\(^o\)

\(^o\)

y 0.0         1.5         -2.6

 

(b) Using a scale of 2 cm to 15ยฐ on the x-axis and 2cm to I unit on the y-axis, draw the graph of y = 3 sin 2x for 0ยฐ \(\geq\) x \(\geq\) 150ยฐ.

(c) Use the graph to find the truth set of;

(i) 3 sin 2x + 2 = 0;

(ii ) \(\frac{3}{2}\) sin 2x = 0.25. 

 

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8

A die was rolled a number of times. The outcomes are as shown in the table 

Number 1 2 3 4 5 6
Outcomes 32 m 25 40 28 45

If the probability of obtaining 2 is 0.15, find the: 

(a) value of m;

(b) number of times the die was rolled;

(c) probability of obtaining an even number. 

 

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9

The total surface area of a cone of slant height 1cm and base radius rcm is 224\(\pi\) cm\(^2\). If r : 1 = 2.5, find: 

(a) correct to one decimal place, the value of r

(b) correct to the nearest whole number, the volume of the cone [Take \(\pi\) = \(\frac{22}{7}\)]

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10

(a} In the diagram, O is the centre of the circle ABCDE, = I\(\overline{BC}\)I = |\(\overline{CD}\)| and < BCD = 108ยฐ. Find < CDE. 

(b) Given that tan x = \(\sqrt{3}\), 0\(^o\) \(\geq\) x \(\geq\) 90\(^o\), evaluate 

\(\frac{(cos x)^2 – sin x}{(sin x)^2 + cos x}\) 
 

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11

(a) Given that P = (\(\frac{rk}{Q} – ms\))\(^{\frac{2}{3}}\)

(i) Make Q the subject of the relation;

(ii) find, correct to two decimal places, the value of Q when P = 3, m = 15, s = 0.2, k = 4 and r = 10.

(b) Given that \(\frac{x + 2y}{5}\) = x – 2y, find x : y

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12

(a) If A = {multiples of 2}, B = {multiples of 3} and C = {factors of 6} are subsets of \(\mu\) = {x:1 \(\leq\) x  \(\leq\)  10} find A โ€ฒ \(\cap\) B โ€ฒ \(\cap\) Cโ€ฒ

(b) Tickets for a movie premiere cost $18.50 each while the bulk purchase price for 5 tickets is $80.00. If 4 gentlemen decide to get a fifth person to join them so that they can share the bulk purchase price equally, how much would each person save?

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13

Find the least value of x which satisfies the equation 4x = 7(mod 9)

  • A. 7
  • B. 6
  • C. 5
  • D. 4
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14

In the diagram, O is the centre of the circle. If < NLM = 74\(^o\), < LMN = 39\(^o\) and < LOM = x, find the value of x. 

  • A. 134\(^o\)
  • B. 126\(^o\)
  • C. 113\(^o\)
  • D. 106\(^o\)
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15

If (x + 2) is a factor of x\(^2\) +px – 10, find the value of P. 

  • A. 3
  • B. -3
  • C. 7
  • D. -7
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16

The graph of the equations y = 2x + 5 and y = 2x\(^2\) + x – 1 are shown. Use the information above to answer this question. 

If x = -2.5, what is the value of u on the curve?

  • A. y = 8.0
  • B. y = 8.5
  • C. y = 9.0
  • D. y = 9.5
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17

The graph of the equations y = 2x + 5 and y = 2x\(^2\) + x – 1 are shown. Use the information above to answer this question.

Find the point of intersection of the two graphs.

  • A. (2.0, 9.0) and (-1.5, 2.0)
  • B. (2.0, 8.5) and (-1.5, 2.0)
  • C. (2.0, 8.0) and (-1.5, 2.5)
  • D. (2.0, 7.5) and (-1.5, 2.5)
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18

The interquartile range of distribution is 7. If the 25th percentile is 16, find the upper quartile.

  • A. 35
  • B. 30
  • C. 23
  • D. 9
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19

A woman received a discount of 20% on a piece of cloth she purchased from a shop. If she paid $525.00, what was the original price?

  • A. $675.25
  • B. $660.25
  • C. $656.25
  • D. $616.25
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20

Which of the following is not a sufficient condition for two triangles to be congruent?

  • A. AAS
  • B. SSS
  • C. SAS
  • D. SSA
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21

In the diagram, O is the center of the circle. \(\overline{PQ}\) and \(\overline{RS}\)  are tangents to the circle. Find the value of (M + N).

  • A. 120\(^o\)
  • B. 90\(^o\)
  • C. 75\(^o\)
  • D. 60\(^o\)
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