Chapter-1 Numbers — Online MCQ Test
MATHS · Samacheer Kalvi 8th · Tamil Nadu State Board
Practice Chapter-1 Numbers with a free chapter-wise online MCQ test.
This chapter covers: rational numbers properties operations Covers rational numbers properties and operations.
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter-1 Numbers — Important Questions & Answers
Which of the following is the correct form of a rational number?
- A. p/q, where p and q are integers and q ≠ 0
- B. p/q, where p and q are integers and q = 0
- C. p/q, where only p is an integer
- D. p/q, where p and q are natural numbers only
Answer: A. p/q, where p and q are integers and q ≠ 0
A rational number is any number that can be written as p/q, where p and q are integers and q is not zero.
A rational number is any number that can be written as p/q, where p and q are integers and q is not zero.
What is the multiplicative inverse of -5/7?
- A. 5/7
- B. -5/7
- C. 7/5
- D. -7/5
Answer: D. -7/5
The multiplicative inverse of a non-zero rational number a/b is b/a. Hence, the inverse of -5/7 is -7/5.
The multiplicative inverse of a non-zero rational number a/b is b/a. Hence, the inverse of -5/7 is -7/5.
Find the value of (-3/4) + (5/6).
- A. 1/12
- B. -1/12
- C. 2/10
- D. 19/12
Answer: A. 1/12
The LCM of 4 and 6 is 12, so -3/4 = -9/12 and 5/6 = 10/12. Their sum is 1/12.
The LCM of 4 and 6 is 12, so -3/4 = -9/12 and 5/6 = 10/12. Their sum is 1/12.
Arrange the rational numbers -5/8, -7/10, 3/4 and 1/2 in ascending order.
- A. -5/8, -7/10, 1/2, 3/4
- B. -7/10, -5/8, 1/2, 3/4
- C. 1/2, 3/4, -5/8, -7/10
- D. -7/10, 1/2, -5/8, 3/4
Answer: B. -7/10, -5/8, 1/2, 3/4
-7/10 = -0.7 and -5/8 = -0.625, so -7/10 is smaller. Among the positive numbers, 1/2 is smaller than 3/4.
-7/10 = -0.7 and -5/8 = -0.625, so -7/10 is smaller. Among the positive numbers, 1/2 is smaller than 3/4.
Find the rational number which must be added to -3/7 to get 5/14.
- A. 1/14
- B. -1/14
- C. 11/14
- D. -11/14
Answer: C. 11/14
Let the required number be x. Then x + (-3/7) = 5/14, so x = 5/14 + 3/7 = 5/14 + 6/14 = 11/14.
Let the required number be x. Then x + (-3/7) = 5/14, so x = 5/14 + 3/7 = 5/14 + 6/14 = 11/14.