JAMB - Mathematics (1982)

1
Rationalize the expression \(\frac{1}{\sqrt{2} + \sqrt{5}}\)
Răspuns
(A)
\(\frac{1}{3}\)(\(\sqrt{5} - \sqrt{2}\)
2
Simplify 3 - 2 \(\div\) \(\frac{4}{5}\) + \(\frac{1}{2}\)
Răspuns
(D)
1
3
If N560.70 is shared in the ratio 7 : 2 : 1, what is the smallest share?
Răspuns
(E)
N56.07
4
Seven years ago, the age of a father was three times that of his son, but in six years time the age of the son will be half that of his father, representing the present ages of the father and son by x and y, respectively, the two equations relating x and y are
Răspuns
(B)
3y - x = 14; x - 2y = 6
5
The factors of 6x - 5 - x2 are
Răspuns
(C)
(x - 5)(1 - x)
6
The solution of the quadratic equation bx\(^2\) + cx + a = 0 is given by
Răspuns
(C)
x = -c \(\pm\) \(\frac{\sqrt{c^2 - 4ab}}{2b}\)
7
The graphical method of solving the equation x3 + 3x2 + 4x - 28 = 0 is by drawing the graphs of the curves
Răspuns
(D)
y = x² + 3x + 4 and y = \(\frac{28}{x}\)
8
Write the equation 2 log2x - x log2(1 + y) = 3 in a form not involving logarithms
Răspuns
(C)
x² = 8(1 + y)^x
9
Find \(\alpha\) and \(\beta\) such that x\(\frac{3}{8}\) x y\(\frac{-6}{7}\) x (\(\frac{y^{\frac{9}{7}}}{x^{\frac{45}{8}}}\))\(\frac{1}{9}\) = \(\frac{y^{\alpha}}{y^{\beta}}\)
Răspuns
(A)
\(\alpha\) = 1, \(\beta\) = \(\frac{5}{7}\)
10
Which of the following lines is not parallel to the line 3y + 2x + 7 = 0?
Răspuns
(D)
3y - 2x + 7 = 0
11
What is the least possible value of \(\frac{9}{1 + 2x^2}\) if 0 \(\geq\) x \(\geq\) 2?
Răspuns
(C)
1
12
A man bought wrist watch for N150 but was only able to sell it for N120. Find the loss per cent on the transaction
Răspuns
(C)
20%
13
Find the median of the set set of numbers 110, 116, 113, 119, 118, 127, 118, 117, 113
Răspuns
(C)
117
14
If f(x - 2) = 3\(x^2\) + 4x + 1. Find (1).
Răspuns
(B)
40
15
A sector of a circle is bounded by two radii 7cm long and an arc length 6cm. Find the area of the sector.
Răspuns
(C)
21cm²
16
Given that p:q = \(\frac{1}{3}\):\(\frac{1}{2}\) and q:r = \(\frac{2}{5}\): \(\frac{4}{7}\) find p:r
Răspuns
(B)
7:15
17
If sin \(\theta\) = \(\frac{m - n}{m + n}\); Find the value of 1 + tan2\(\theta\)
Răspuns
(B)
\(\frac{(m^2 + n^2 + 2mn)}{4mn}\)
18
The currency used in a country is called 'Matimalik'(M) and is of base seven. A lady in that country bought 4 bags of rice at M56 per bag and and 3 tins of milk at M4 per tin. What is the total cost of the item she bought?
Răspuns
(D)
M341₇
19
Solve for x, If \(\frac{\frac{2}{x}}{\frac{1}{p^2} + \frac{1}{q^2}}\) = m
Răspuns
(B)
\(\frac{2p^2q^2}{m(q^2 + p^2)}\)
20
Express 37.05 x 0.0042 in standard form
Răspuns
(C)
1.556 x 10^-1
21
Find the values of x for which the expression \(\frac{(x - 3)(x - 2)}{x^2 + x - 2}\) is undefined?
Răspuns
(A)
1, -2
22
A stone Q is tied to a point P vertically above Q by an inelastic string of length 2 meters. How high does the stone rise when the string is inclined at an angle 60^o to the vertical?
Răspuns
(D)
1 meters
23
Express 130 kilometers per second in meters per hour
Răspuns
(D)
4.68 x 10⁸
24
The quantity y is partly constant and partly varies inversely as the square of x. With P and Q as constants, a possible relationship between x and y is
Răspuns
(A)
y = Q + \(\frac{P}{x^2}\)
25
If \(\frac{3e + f}{3f - e}\) = \(\frac{2}{5}\), find the value of \(\frac{e + 3f}{f - 3e}\)
Răspuns
(C)
\(\frac{26}{7}\)
26
A world congress of mathematicians were held in Nice in 1970 with 800 people participating. There were 300 from Europe, 200 from America, 150 from Asia, 45 from Africa and 105 from Australia. Representing the above on a pie chart, the angle of the sector representing the participants from Asia is?
Răspuns
(B)
67\(\frac{1}{2}\)^o
27
The diameter of a metal rod is measured as 23.40 cm to four significant figures. What is the maximum error in the measurement?
Răspuns
(D)
0.005cm
28
In a regular polygon of n sides, each interior angle is 144o. Find n
Răspuns
(C)
10
29
Simplify \(\frac{3}{2x - 1}\) + \(\frac{2 - x}{x - 2}\)
Răspuns
(C)
\(\frac{4 - 2x}{2x - 1}\)
30
The solution to the quadratic equation 5 + 3x - 2x² = 0 is
Răspuns
(D)
(\(\frac{5}{2}\), -1)
31
A housewife bought 3 kilograms of garri at N13.00 per kg. She deposited N160. 00 for half a cow and bought 24 oranges at 10k each. She came back home with N20.60. She therefore left home with
Răspuns
(B)
N222.00
32
The solution to the simultaneous equations 3x + 5y = 4, 4x + 3y = 5 is
Răspuns
(B)
(\(\frac{13}{11}, \frac{1}{11}\))
33
The area of the curved surface of the cone generated by the sector of a circle radius 6cm and arc length 22cm is (\(\pi\) = \(\frac{22}{7}\))
Răspuns
(E)
66 sq.cm
34
The square base of a pyramid of side 3cm has height 8cm. If the pyramid is cut into two parts by a plane parallel to the base midway between the base and the vertex, the volumes of the two sections are
Răspuns
(B)
(24cm³, 3cm³)
35
Simplify f\(^{\frac{1}{2}}\)g\(^2\)h\(^{\frac{1}{3}}\) \(\div\) f\(^{\frac{5}{2}}\)g\(^o\)h\(^{\frac{7}{3}}\)
Răspuns
(A)
(\(\frac{g}{fh}\))²
36
Determine the mean monthly salary of 50 employees of a company from the following frequency distribution.
\(\begin{array}{c|c} \text{Monthly salary} & \text{Frequency}\\\hline N200.00 & 10\\ N325.00 & 5\\N100.00 & 20\\N120.00 & 2\\ N60.00 & 10\\ N80.00 & 3\end{array}\)
Răspuns
(B)
N134.10
37
If the function y = 5x is graphed, what would be its intercept on the y-axis?
Răspuns
(E)
zero
38
A side of a rhombus is 2cm in length. An angle of the rhombus is 60^o. What is the length of the diagonal facing this angle?
Răspuns
(D)
2\(\sqrt{3}\)cm
39
A variable y is inversely proportional to x², when y = 10, x = 2. What is y when x = 10?
Răspuns
(D)
0.4
40
Two distinct sectors i the same circle substend 100^o and 30^o respectively at the centre of the circle. Their corresponding arcs are in ratio
Răspuns
(A)
10:3
41
The arithmetic mean of the ages of 30 pupils in a class is 15.3 years. One boy leaves the class and one girl is enrolled, and the new average age of 30 pupils in the class becomes 15.2 years. How much older is the boy than the girl?
Răspuns
(D)
3 years
42
In the diagram, angle QPR = 90^o, angle PSR = 90^o and PR = 5 units. Find the length of QS.
Răspuns
(C)
5 tan 25^o cos 65^o
43
The diagram is the distance time graph of a vehicle. Find its average speed in kilometers per hour during the journey
Răspuns
(E)
84km/hr
44
In the fiqure where PQRTU is a circle, ISTI = IRSI and angle TSR = 52^o. Find the angle marked m
Răspuns
(E)
116^o
45
If K is a constant, which of the following equations best describes the parabola?
Răspuns
(B)
x = y² - k