2006 - JAMB Mathematics Past Questions and Answers - page 1
The question will be answered in
(^5C_4 = \frac{6!}{(6-4)!4!}=\frac{6!}{2!4!}=\frac{6\times5\times4!}{2\times1\times4!}=15\hspace{1mm}ways)
Users' Answers & CommentsLet the consecutive numbers be a, a+1, a+2, a+3, a+4
Mean = (\frac{(a+a+1+a+2+a+3+a+4)}{5}\
30 = \frac{5a+10}{5}\
30 \times 5 = 5a + 10\
5a = 150 - 10\
5a = 140\
a = 28 \
∴ a + 4 = 28 + 4\
= 32)
Users' Answers & CommentsBlack = 5
White = 4
Red = x
Total = 9+x
P(red) = 2/3
x / (9+x) = 2/5
5x = 2(9+x)
5x = 18+2x
5x-2 = 18
3x = 18
x = 6
Users' Answers & Comments(\sum x = 6x\
\sum(x-\bar{x})^2 = 2\
\bar{x} = \frac{\sum x}{n}\
= \frac{6x}{3}\
= 2x\
Variance = \frac{\sum(x-\bar{x})^2}{n}\
= \frac{2}{3})
Users' Answers & Comments
P(GTN) = 5/20
P(Qtel) = 3/20
∴P(GTN or Qtel) = (5/20) + (3/20)
= 8/20
= 2/5
Users' Answers & Comments
Expenditure on housing = x
Expenditure on food = 2x
Expenditure on school fees = 90o
Expenditure on transport = 45o
x + 2x + 90 + 45 = 360o
3x + 135 = 360o
3x = 360 - 135
3x = 225
x = 225/3 = 75o
∴∠ for food = 2x = 2 * 75
= 150
360o = N30,000
1o = ?
1o = 30,000/360
150o = (30000/360) * (150/1)
= N12500
Users' Answers & Comments(^{n+1}C_3 = 4(^nC_3)\frac{(n+1)!}{(n+1-3)!3!} = 4\left(\frac{n!}{(n-3)!3!}\right)\frac{(n+1)n!}{(n-2)(n-3)!}=4\left(\frac{n!}{n-3!}\right)=\frac{n+1}{n-2}=\frac{4}{1}\n+1 = 4(n-2)\n+1 = 4n-8-3n = -9\frac{-9}{-3}\n=3)
Users' Answers & Commentsdy/dx = 2x + 7
y = ∫2x + 7
y = x2 + 7x + C at (2,0)
0 = 22 + 7(2) + C
0 = 4 + 14 + C
0 = 18 + C
C = -18
∴ The equation is y = x2 + 7x - 18
Users' Answers & Commentsy = (x2 - 1/x)2
y = (x2 - 1/x)(x2 - 1/x)
y = x4 - x - x + 1/x2
y = x4 - 2x + 1/x2
y= x4 - 2x + x-2
dy/dx = 4x2 - 2 - 2x-3
= 4x2 - 2 - 2/x3
Users' Answers & Comments