Area problems
- 1. The perimeter of a square is equal to twice the perimeter of a rectangle of length 8cm and breadth 7cm. What is the circumference of a semicircle whose diameter is equal to the side of the square ?
Options- A. 55.12 cm
- B. 22.54 cm
- C. 42.51 cm
- D. 38.57 cm Discuss
Correct Answer: 38.57 cm
Explanation:
We know that perimeter of rectangle = 2(l+b) = 2(8+7)= 30cm
Given perimeter of square is twice the perimeter of rectangle = 2(30) = 60cm
Therefore, side of the square is = 1/4 x 60 = 15cm
Circumference of the required semicircle =
=
= 23.57 + 15 = 38.57cm.
- 2. If a 36 cm thread is used to wrap a book, lengthwise twice and breadth wise once, what is the size of the book ?
Options- A. 288 sq.cm
- B. 188 sq.cm
- C. 144 sq.cm
- D. 244 sq.cm Discuss
Correct Answer: 288 sq.cm
Explanation:
Length of the thread is 36 cms.
length wise twice breath wise once then totally thrice.
so 36/3 = 12.
so length is 12 x 2 = 24 cms
breath is 12 cms
Area of the book = length x breath = 24 x 12 = 288 sq.cm
- 3. Let A(O,-1), B(0,3) and C(2,1) be three points. Let ?1 be the area of the triangle ABC and ?2 be the area of the triangle formed by the mid points of the sides of the triangle whose vertices are A, B and C such that ?1 =1 , ?2=x Find the value of x .
Options- A. 4
- B. 5
- C. 2
- D. 3 Discuss
Correct Answer: 3
- 4. A man walking at the speed of 4 kmph crosses a square field diagonally in 3 meters.The area of the field is
Options- A. 10000
- B. 20000
- C. 30000
- D. 40000 Discuss
Correct Answer: 20000
Explanation:
speed of the man = 4 x (5/18) m/sec = 10/9 m/sec
time taken = 3 x 60 sec = 180 sec
length of diagonal = speed x time = (10/9) x 180 = 200m
Area of the field = (1/2) x (dioagonal)²
= (1/2) x 200 x 200 sq.m = 20000sq.m
- 5. If the ratio of two squares is 225:256,then the ratio of the perimeters is
Options- A. 25:16
- B. 15:16
- C. 16:15
- D. 17:16 Discuss
Correct Answer: 15:16
Explanation:
- 6. The area of a square is 1024 sq.cm. What is the ratio of the length to the breadth of a rectangle whose length is twice the side of the square and breadth is 12 cm less than the side of this square ?
Options- A. 14:9
- B. 13:12
- C. 16:5
- D. 17:13 Discuss
Correct Answer: 16:5
Explanation:
Area of a square SxS = 1024 => S = 32 cm
Length of the rectangle = 32x2 cm = 64 cm
Breadth of the rectangle = 32 - 12 = 20 cm
Required ratio = 64 : 20 = 16 : 5
- 7. A rectangular grassy plot 120 m. by 60 m has a gravel path 1.5 m wide all round it on the inside. Find the cost of gravelling the path at 65 paise per sq. metre ?
Options- A. Rs. 345.15
- B. Rs. 245.1
- C. Rs. 234.18
- D. Rs. 456.65 Discuss
Correct Answer: Rs. 345.15
Explanation:
area of the plot = 120m x 60m = 7200 sq.m
area of plot excluding gravel = 117m x 57m = 6669 sq.m
area of gravel = 7200 sq.m - 6669 sq.m = 531 sq.m
cost of building it = 531 sq.m x 65 ps = 34515 ps
In Rs. = 34515/100 = Rs. 345.15.
- 8. The perimeter of an isosceles triangle is 32 cm and each of the equal sides is 5/6 times of the base. What is the area (in cm2 ) of the triangle ?
Options- A. 39
- B. 48
- C. 57
- D. 64 Discuss
Correct Answer: 48
- 9. The ratio between the length and breadth of a rectangular field is 5 : 4 if the breadth is 20m less than the length, the perimeter of the field is :
Options- A. 260m
- B. 280m
- C. 360m
- D. none of these Discuss
Correct Answer:
- 10. The wheel of a motorcycle 70cm in diameter makes 40 revolutions in every 10sec.What is the speed of motorcycle n km/hr?
Options- A. 13.68kmph
- B. 31.68kmph
- C. 41.68kmph
- D. 45.68kmph Discuss
Correct Answer: 31.68kmph
Explanation:
In this type of question, we will first calculate the distance covered in given time.
Distance covered will be : Number of revolutions x Circumference
So we will be having distance and time, from which we can calculate the speed.
Radius of wheel = 70 / 2 = 35 cm
Distance covered in 40 revolutions will be = 88 m
Distance covered in 1 sec =
More in Aptitude:
Programming
Copyright ©CuriousTab. All rights reserved.