WAEC - Mathematics (1991)

  • 1
    Express 0.0462 in standard form
    תְשׁוּבָה
    (D)
    4.62 x 10-2
  • 2
    The population of a village is 5846. Express this number to three significant figures
    תְשׁוּבָה
    (A)
    5850
  • 3
    Simplify: log6 + log2 - log12
    תְשׁוּבָה
    (C)
    0
  • 4
    Find the number whose logarithm to base 10 is 2.6025
    תְשׁוּבָה
    (A)
    400.4
  • 5
    Simplify: \((\frac{1}{4})^{-1\frac{1}{2}}\)
    תְשׁוּבָה
    (E)
    8
  • 6
    For what value of y is the expression \(\frac{y + 2}{y^{2} - 3y - 10}\) undefined?
    תְשׁוּבָה
    (D)
    y = 5
  • 7
    Factorize 3a\(^2\) - 11a + 6
    תְשׁוּבָה
    (A)
    (3a - 2)(a - 3)
  • 8
    Solve the equation: 3a + 10 = a\(^2\)
    תְשׁוּבָה
    (E)
    a = 5 or a = -2
  • 9
    Simplify \((\frac{3}{x} - \frac{15}{2y}) \div \frac{6}{xy}\)
    תְשׁוּבָה
    (A)
    \(\frac{2y - 5x}{4}\)
  • 10
    Simplify: \(\frac{1}{4}(2^n  - 2^{n + 2}\))
    תְשׁוּבָה
    (A)
    \(2^{n - 2} - 2^n\)
  • 11
    Find the equation whose roots are -2/3 and -1/4
    תְשׁוּבָה
    (A)
    12x2 + 11x + 2 = 0
  • 12
    Solve: 6(x - 4) + 3(x + 7) = 3
    תְשׁוּבָה
    (B)
    2/3
  • 13
    If 2x + y = 7 and 3x - 2y = 3, by how much is 7x greater than 10?
    תְשׁוּבָה
    (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
    תְשׁוּבָה
    (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
    תְשׁוּבָה
    (C)
    N545
  • 16
    A car is travelling at an average speed of 80km/hr. Its speed in meters per second (m/s) is
    תְשׁוּבָה
    (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.
    תְשׁוּבָה
    (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

    תְשׁוּבָה
    (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 \(\pi\) = \(\frac{22}{7}\) )

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

    Find the coordinates of point B

    תְשׁוּבָה
    (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.
    תְשׁוּבָה
    (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,
    תְשׁוּבָה
    (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).
    תְשׁוּבָה
    (D)
    πR/3
    cos4o
  • 25

    the graph above is a sketch of

    תְשׁוּבָה
    (B)
    y=sinx
  • 26
    Given that sin \(\theta\) = -0.9063, where O \(\leq\) \(\theta\) \(\leq\) 270°, find \(\theta\).
    תְשׁוּבָה
    (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.
    תְשׁוּבָה
    (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
    תְשׁוּבָה
    (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

    תְשׁוּבָה
    (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
    תְשׁוּבָה
    (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
    תְשׁוּבָה
    (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?
    תְשׁוּבָה
    (C)
    35
  • 33
    Which of the following is not a measure of dispersion?
    תְשׁוּבָה
    (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
    תְשׁוּבָה
    (B)
    4
  • 35

    Find the mean of the distribution

    תְשׁוּבָה
    (C)
    4.4
  • 36
    Find the mode of the distribution
    תְשׁוּבָה
    (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

    תְשׁוּבָה
    (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

    תְשׁוּבָה
    (A)
    0
  • 39
    If events X and Y are mutually exclusive, P(X) = 1/3 and P(Y) = 2/5, P(X∪Y) is
    תְשׁוּבָה
    (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?
    תְשׁוּבָה
    (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?
    תְשׁוּבָה
    (A)
    1/8
  • 42
    Which of the following about a rhombus may not be true?
    תְשׁוּבָה
    (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.
    תְשׁוּבָה
    (D)
    80
  • 44

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

    תְשׁוּבָה
    (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?
    תְשׁוּבָה
    (D)
    8