2014 - JAMB Mathematics Past Questions and Answers - page 5
Numbers & 1 & 2 & 3 & 4 & 5 & 6 \\ \hline
Frequency & 18 & 22 & 20 & 16 & 10 & 14
\end{array}\)
The table above represents the outcome of throwing a die 100 times. What is the probability of obtaining at least a 4?
Let E demote the event of obtaining at least a 4
Then n(E) = 16 + 10 + 14 = 40
Hence, prob (E) = (\frac{n(E)}{n(S)})
( = \frac{40}{100})
( = \frac{2}{5})
Users' Answers & CommentsSample space S = {10, 11, 12, ... 30}
Let E denote the event of choosing a number divisible by 3
Then E = {12, 15, 18, 21, 24, 27, 30} and n(E) = 7
Prob (E) = (\frac{n(E)}{n(E)})
Prob (E) = (\frac{7}{21})
Prob (E) = (\frac{1}{3})
Users' Answers & Comments

In the diagram above, (\alpha) = 54o(alternate angles; KL||MN) < KNM = 2(\alpha) (LN is bisector of < KNM) = 108o
35o + < KMN + 108o = 180o(sum of angles of (\bigtriangleup))
< KMN + 143o = 180o
< KMN = 180o - 143o
= 37o
Users' Answers & Comments
In the figure above, qo = 30o (vertically opposite angles)
(P + 2q)o + 30o = 180o(angles on a straight line)
p + 2 x 30o + 30o = 180o
p + 60o + 30o = 180o
p + 90o = 180o
p = 180o - 90o
= 90o
Users' Answers & Comments
In the figure above, (\frac{x}{\sin 60^o} = \frac{10}{\sin 30^o}) (Sine rule)
x = (\frac{10 \sin 60^o}{\sin 30^o})
= 10 x (\frac{\sqrt{3}}{2} \times \frac{1}{2})
= 10 x (\frac{\sqrt{3}}{2} \times \frac{2}{1})
= 10(\sqrt{3})cm
Users' Answers & Comments
(x1, y1) = (0,5)
(x2, y2) = (5, 0)
Using (\frac{y - y_1}{y_1 - y_1} = \frac{x - x_1}{x_1 - x_1})
(\frac{y - 5}{0 - 5} = \frac{x - 0}{5 - 0})
(\frac{y - 5}{-5} = \frac{x}{5})
5(y - 5) = -5x
y - 5 = -x
x + y = 5
y = -x + 5
Users' Answers & Comments
Angle of sector subtended by yam
= 360o - (70 + 80 + 50)o
= 360o - 200o
= 160o
But (\frac{80^o}{360^o}) x T = 8000
T = (\frac{8000 \times 360^o}{80^o})
= N36,000
Hence the amount spent on yam = (\frac{160^o}{260} \times N36,000)
= N16,000
Users' Answers & Comments