Q1. If the side of the square is increased by 30%, then how much % does its area get increased?
A. 59%
B. 69%
C. 79%
D. 49%
Answer: B
Explanation:
Area of the plot = [latex] 1.3 \times 1.3 = 1.69 = 69 % [/latex]
Q2. A ladder is resting with one end in contact with the top of the wall of height 15m and the other end of the ground is at a distance 8m from the wall. The length of the ladder is?
A. 17m
B. 18m
C. 16m
D. 15m
Answer: A
Explanation:
Hypotenuse = [latex] \sqrt {(base)² + (altitude)²} [/latex]
[latex] \sqrt {(8)² + (15)²} = \sqrt {289} [/latex] = 17 m
Q3. The perimeter of a square is equal to twice the perimeter of a rectangle of length 10 cm and breadth 4 cm. What is the circumference of a semi-circle whose diameter is equal to the side of the square?
A. 38 cm
B. 23 cm
C. 46 cm
D. 36 cm
Answer: D
Explanation:
Perimeter of square = 2(l + b)
= [latex] 2 \times 2(10 + 4) = 2 \times 28 [/latex] = 56 cm
Side of square = [latex] \frac {56}{4} [/latex] = 14 cm
Radius of semi circle = [latex] \frac {14}{2} [/latex] = 7cm
Circumference of the semi-circle = [latex] \frac {22}{7} \times 7 + 14 [/latex] = 36 cm
Q4. The length of a rectangle is [latex] \frac {3}{{5}^{th}} [/latex] of the side of a square. The radius of a circle is equal to the side of the square. The circumference of the circle is 132 cm. What is the area of the rectangle, if the breadth of the rectangle is 15 cm?
A. 112 cm²
B. 149 cm²
C. 189 cm²
D. Cannot be determined
Answer: C
Explanation:
Circumference of the circle = 132
[latex] 2 \pi R [/latex] = 132;
R = 21 cm
Side of square = 21 cm
Length of the rectangle = [latex] \frac {3}{5} \times 21 = \frac {63}{5} [/latex]
Area of the rectangle = [latex] \frac {63}{5} \times 15 [/latex] = 189 cm²
Q5. Smallest side of a right-angled triangle is 13 cm less than the side of a square of perimeter 72 cm. The second-largest side of the right-angled triangle is 2 cm less than the length of the rectangle of area 112 cm² and breadth 8 cm. What is the largest side of the right-angled triangle?
A. 20 cm
B. 12 cm
C. 10 cm
D. 13 cm
Answer: D
Explanation:
Side of square = [latex] \frac {72}{4} [/latex] = 18 cm
Smallest side of the right angled triangle = 18 – 13 = 5 cm
Length of rectangle = [latex] \frac {112}{8} [/latex] = 14 cm
Second side of the right angled triangle = 14 – 2 = 12 cm
Hypotenuse of the right angled triangle = [latex] \sqrt {(25 + 144)} [/latex] = 13cm