WAEC - Mathematics (1991)

  • 1
    Express 0.0462 in standard form
    Trả lời
    (D)
    4.62 x 10-2
  • 2
    The population of a village is 5846. Express this number to three significant figures
    Trả lời
    (A)
    5850
  • 3
    Simplify: log6 + log2 - log12
    Trả lời
    (C)
    0
  • 4
    Find the number whose logarithm to base 10 is 2.6025
    Trả lời
    (A)
    400.4
  • 5
    Simplify: \((\frac{1}{4})^{-1\frac{1}{2}}\)
    Trả lời
    (E)
    8
  • 6
    For what value of y is the expression \(\frac{y + 2}{y^{2} - 3y - 10}\) undefined?
    Trả lời
    (D)
    y = 5
  • 7
    Factorize 3a\(^2\) - 11a + 6
    Trả lời
    (A)
    (3a - 2)(a - 3)
  • 8
    Solve the equation: 3a + 10 = a\(^2\)
    Trả lời
    (E)
    a = 5 or a = -2
  • 9
    Simplify \((\frac{3}{x} - \frac{15}{2y}) \div \frac{6}{xy}\)
    Trả lời
    (A)
    \(\frac{2y - 5x}{4}\)
  • 10
    Simplify: \(\frac{1}{4}(2^n  - 2^{n + 2}\))
    Trả lời
    (A)
    \(2^{n - 2} - 2^n\)
  • 11
    Find the equation whose roots are -2/3 and -1/4
    Trả lời
    (A)
    12x2 + 11x + 2 = 0
  • 12
    Solve: 6(x - 4) + 3(x + 7) = 3
    Trả lời
    (B)
    2/3
  • 13
    If 2x + y = 7 and 3x - 2y = 3, by how much is 7x greater than 10?
    Trả lời
    (C)
    7
  • 14
    A cylinder of base radius 4cm is open at one end . If the ratio of the area of its base to that of its curved surface is 1:4, calculate the height of the cylinder
    Trả lời
    (D)
    8cm
  • 15
    A headmaster contributes 7% of his income into a fund and his wife contributes 4% of her income. If the husband earns N5,500 per annum (p.a) and the wife earns N4,000 (P.a), find the sum of their annual contribution to the fund
    Trả lời
    (C)
    N545
  • 16
    A car is travelling at an average speed of 80km/hr. Its speed in meters per second (m/s) is
    Trả lời
    (B)
    22.2m/s
  • 17
    Mrs. Kofi sold an article for C7.50 instead of C12.75. Calculate her percentage of error, correct to one decimal place.
    Trả lời
    (A)
    41.2%
  • 18

    In the diagram above, PXR and PYO are two semi-circles with diameters 14cm and 7cm respectively. Find the area of the enclosed region, PXROY correct to the nearest whole number

    Trả lời
    (A)
    96cm2
  • 19

    In the diagram above, PXR and PYO are two semicircles with diameters 14cm and 7cm respectively. Find the perimeter of the region (take \(\pi\) = \(\frac{22}{7}\) )

    Trả lời
    (C)
    40cm
  • 20
    The shaded portion shows the outer boundary
    of the half plane defined by the inequality
    Trả lời
    (A)
    4x + 3y \(\geq\) 6
  • 21

    Find the coordinates of point B

    Trả lời
    (E)
    (11/2, 0)
  • 22
    The first term a of an A.P is equal to twice the
    common difference d. Find, in terms of d, the 5th
    term of the A.P.
    Trả lời
    (C)
    6d
  • 23
    The common ratio of a G.P. is 2. If the 5th term is
    greater than the 1st term by 45, find the 5th term,
    Trả lời
    (D)
    48
  • 24
    Two towns, P and Q, are on (4oN 40oW) and (4oN
    20oE) respectively. What is the distance between
    them, along their line of latitude? (Give your
    answer in teems of π and R, the radius of the earth).
    Trả lời
    (D)
    πR/3
    cos4o
  • 25

    the graph above is a sketch of

    Trả lời
    (B)
    y=sinx
  • 26
    Given that sin \(\theta\) = -0.9063, where O \(\leq\) \(\theta\) \(\leq\) 270°, find \(\theta\).
    Trả lời
    (D)
    245o
  • 27
    From the top of a cliff, the angle of depression of
    a boat on the sea is 60o, if the top of the cliff is
    25m above the sea level, calculate the horizontal
    distance from the bottom of the cliff to the boat.
    Trả lời
    (C)
    25√3m/3
  • 28
    The angle of elevation of the top of a tree 39m
    away from a point on the ground is 30o. Find the height of the tree
    Trả lời
    (B)
    13√3m
  • 29

    In the diagram above, ATR is a tangent at the point T to the circle center O, if ∠TOB = 145°, find ∠TAO

    Trả lời
    (D)
    55o
  • 30
    P={2, 1,3, 9, 1/2}; Q = {1,21/2,3, 7} and R = {5, 4, 21/2}. Find P∪Q∪R
    Trả lời
    (E)
    (1/2, 1, 2, 21/2, 3, 4, 5, 7, 9)
  • 31
    P = {2, 1,3, 9, 1/2}; Q = {1,21/2,3, 7} and R = {5, 4, 21/2}. Find P∩Q∩R
    Trả lời
    (B)
  • 32
    In a class of 80 students, every student had to study Economics or Geography or both Economics and Geography. lf 65 students studied Economics and 50 studied Geography, how many studied both subjects?
    Trả lời
    (C)
    35
  • 33
    Which of the following is not a measure of dispersion?
    Trả lời
    (A)
    Mode
  • 34
    The mean of 30 observations recorded in an experiment is 5. lf the observed largest value of 34 is deleted, find the mean of the remaining observations
    Trả lời
    (B)
    4
  • 35

    Find the mean of the distribution

    Trả lời
    (C)
    4.4
  • 36
    Find the mode of the distribution
    Trả lời
    (D)
    5
  • 37
    No. of chairs 1 2 3 4 5 6 7
    Frequency 2 7 5 4 9 7 6

    Find the median of the distribution

    Trả lời
    (C)
    5
  • 38

    If two events are mutually exclusive, their intersection is empty. This means that there are no outcomes that are common to both events. In probability terms, if X and Y are mutually exclusive events, then:

    Pr(X ∩ Y) = 0

    Trả lời
    (A)
    0
  • 39
    If events X and Y are mutually exclusive, P(X) = 1/3 and P(Y) = 2/5, P(X∪Y) is
    Trả lời
    (D)
    11/15
  • 40
    A box contains 2 white and 3 blue identical marbles. If two marbles are picked at random, one after the other without replacement, what is the probability of picking two marbles of different colors?
    Trả lời
    (B)
    3/5
  • 41
    Mrs. Jones is expecting a baby. The probability that it will be a boy is 1/2 and probability that the baby will have blue eyes is 1/4. What is the probability that she will have a blue-eyed boy?
    Trả lời
    (A)
    1/8
  • 42
    Which of the following about a rhombus may not be true?
    Trả lời
    (A)
    The diagonals are equal
  • 43
    The angles of a pentagon are x°, 2x°, (x + 60)°, (x + 10)°, (x -10)°. Find the value of x.
    Trả lời
    (D)
    80
  • 44

    In the diagram above, ∠PTQ = ∠URP = 25° and XPU = 4URP. Calculate ∠USQ.

    Trả lời
    (D)
    130o
  • 45
    In a given regular polygon, the ratio of the exterior angle to the interior angles is 1:3. How many side has the polygon?
    Trả lời
    (D)
    8