# Mathematics Solved Past Paper 9th Class 2012 Karachi Board

Mathematics Solved Past Paper 9th Class 2012 Karachi Board

Mathematics Solved Past Paper 9th Class 2012 Karachi Board

NOTE: Answer 10 questions from this section.

2. If A = {2, 4, 6} and B = {x, y} find A x B.

A = {2, 4, 6} B = {x, y}
A x B = {2, 4, 6} x {x, y}
A x B = {(2, x), (2, y), (4, x), (4, y), (6, x), (6, y)} Ans.

Question no.3

4. Divide 450 rupees among Ahmed, Bashir & Jamil in the ratio of 2, 3 and 4 respectively.

Rate of the shares 2 : 3 : 4
Sum of the ratios 2 + 3 + 4 = 9
Amount to be distributed = 450
Share of Ahmed = 450 x 2/9 = 100
Share of Bashir = 450 x 3/9 = 150
Share of Jamil = 450 x 4/9 = 200.

Question no.5

6. Factorize the following:
(i) ax + ay – 4x – 4y (ii) X² – 10x + 21

(i) ax + ay – 4x – 4y
= a (x + y) -4 (x + y)
= (x + y)(a – 4)

(ii) X² – 10x + 21
= X² – 7x – 3x + 21
= x (x – 7) -3 (x – 7)
= (x – 7) (x – 3)

7. The length of the arc of the sector of a circle is 42 meters and diameter of the circle is 60 meters. Find the area of the sector.

Length of the arc = 42 metre
Diameter of circle = 60 metre
Area of the sector = ?
Formula:
Area of sector = ½ (length x Breadth) = ½ (length of sector x Radius of circle)
Radius = D/2 = 60/2 = 30 metre
:. area = ½ x 42 x 30 = 630 metre Ans.

Question no.8

Question no.9

11. The number of attendance of a student in 6 months is 36, 46, 48, 20, 47, 45 respectively. Find the median of attendance.

Attendance is
20,36,45, 46,47,48
There is no number in between
Median will be
45+46
2
= 45.5 Ans.

12. Convert 11102 into decimal system.

1110² = (1 X 2³) + (1 X 2²) + (1 X 2¹) + (0 x 2°)
= (1 x 8) + (1 x 4) + (1 x 2) + (0 x 1)
= 8 + 4 + 2 + 0
= 14
= 14¹° Ans.

Question no.13

Question no.14

Question no.15

16. Find the continued product with the help of formula: (2 – x)(2 + x)(4 + x²)

(2 – x){2 + x)(4 + x²)
Let 2 = a
X=b
Now (a – b) (a + b) = a² – b²
= (2 – x) (2 + x) (4 + x2)
= (2)² – (x)² (4 + x²)
= (4 – x²) (4 + x²)
= (4)² _ (x²)²
= 16 – x4.

NOTE: Answer any 3 questions from this Section. Question No. 19 is compulsory.

Question no.17

Question no.17 (ii)

18. A person dies leaving behind him a ‘Tarka’ worth Rs.30,000. Distribute the Tarka among 4 sons and 3 daughters. So that each Daughter gets half of what a son gets. Find the share of each when a debt of Rs.8,000 is also paid from Tarka.

Amount of Tarka = 30,000
Amount of Debt = 8,000
Number of sons = 4
Number of daughter = 3
Each son gets twice that of a daughter.

SOLUTION:
Amount left after paying back debt = 30,000 – 8,000 = 22,000
Suppose each daughter gets Re.1
Suppose each son gets Rs.2
3 daughters get 3 x 1 = 3 Rs.
4 sons get 4 x 2 = 8 Rs.
Total amount = 3 + 8 = 11
Share of 3 daughters = 22,000 x 3111 = 6,000
So each daughter gets = 6.000/3 = Rs.2,000
Share of 4 sons = 22,000 x 8/11= 16,000
Share of each son = 16,000/4 = Rs.4,000
Hence,
Share of each daughter = Rs.2,000
Share of each son = Rs.4,000.

Question no.19

Question no.20

Question no.21

Posted on December 17, 2015 in 2012 Karachi Board Past Papers