Section A: Multiple Choice Questions
Which of the following is an irrational number? a) 5 b) 0.75 c) √7 d) 2/3
Which of the following is a terminating decimal? a) 0.333... b) 0.125 c) 0.272727... d) 0.428571...
Find the value of 'a' if (a - 3)² = 36. a) 6 b) 9 c) -6 d) -9
What is the value of x in the equation 3x + 8 = 20? a) 4 b) 6 c) 12 d) 24
Which of the following is not a prime number? a) 17 b) 23 c) 29 d) 33
Section B: Short Answer Questions
Simplify the expression: 3(x - 4) + 2(3x + 2).
Find the HCF and LCM of 36 and 48.
A number when divided by 7 leaves a remainder of 5. Find the possible values of the number.
Solve the equation: 2(3x + 4) - 5(2x - 3) = 4(2x + 1).
Section C: Long Answer Questions
The perimeter of a rectangular field is 180 meters, and its length is 50 meters. Find its width.
The sum of two consecutive odd numbers is 56. Find the numbers.
A tank can be filled by two pipes in 10 hours and 12 hours, respectively. If both pipes are opened simultaneously, how long will it take to fill the tank?
Note: This test is designed to assess your understanding of the concepts covered in Chapters 1, 2, and 3 of the NCERT math book for Class 8.
Certainly! Here are the answers to the math test:
Section A: Multiple Choice Questions
- c) √7
- b) 0.125
- a) 6
- a) 4
- d) 33
Section B: Short Answer Questions
Simplify the expression: 3(x - 4) + 2(3x + 2). Simplifying, we get: 3x - 12 + 6x + 4 = 9x - 8.
Find the HCF and LCM of 36 and 48. The HCF of 36 and 48 is 12. The LCM of 36 and 48 is 144.
A number when divided by 7 leaves a remainder of 5. Find the possible values of the number. The possible values of the number are of the form 7k + 5, where k is an integer.
Solve the equation: 2(3x + 4) - 5(2x - 3) = 4(2x + 1). Simplifying the equation, we get: 6x + 8 - 10x + 15 = 8x + 4. Solving further, we get: -4x + 23 = 8x + 4. Rearranging terms, we get: 12x = 19. Therefore, x = 19/12.
Section C: Long Answer Questions
The perimeter of a rectangular field is 180 meters, and its length is 50 meters. Find its width. Let the width of the rectangular field be 'w.' Perimeter = 2(length + width) 180 = 2(50 + w) 180 = 100 + 2w 2w = 180 - 100 2w = 80 w = 40 meters
The sum of two consecutive odd numbers is 56. Find the numbers. Let the first odd number be 'x.' The second odd number is 'x + 2' since it is consecutive. According to the given condition, x + (x + 2) = 56. Simplifying, we get: 2x + 2 = 56. 2x = 56 - 2 2x = 54 x = 54/2 x = 27 The first odd number is 27, and the second odd number is 27 + 2 = 29.
A tank can be filled by two pipes in 10 hours and 12 hours, respectively. If both pipes are opened simultaneously, how long will it take to fill the tank? Let the combined filling rate of both pipes be 'r.' Pipe 1 can fill the tank in 10 hours, so its filling rate is 1/10 tank per hour. Pipe 2 can fill the tank in 12 hours, so its filling rate is 1/12 tank per hour. The combined filling rate of both pipes is given by: r = 1/10 + 1/12. LCM of 10 and 12 is 60. r = (6/60) + (5/60) = 11/60. Therefore, the tank will be filled in 60/11 hours (approximately 5.45 hours).