Number Play — Practice

Q1. In the chapter, an even number is defined as a number that

• A. Can be arranged in pairs without any leftover.
• B. Is always greater than 10.
• C. Ends with the digit 5.
• D. Is one more than a collection of pairs.

Q2. According to the chapter, an odd number is one which

• A. Is divisible by 3.
• B. Is one more than a collection of pairs.
• C. Always ends with the digit 0.
• D. Is the sum of two even numbers.

Q3. The sum of two even numbers is always

• A. Odd
• B. Sometimes odd, sometimes even
• C. Even
• D. Zero

Q4. The sum of two odd numbers is always

• A. Odd
• B. Even
• C. Zero
• D. A prime number

Q5. The sum of one even number and one odd number is always

• A. Odd
• B. Even
• C. Divisible by 4
• D. A multiple of 3

Q6. In a 3 × 3 magic square filled using the numbers 1 to 9 (each used once), the magic sum is

• A. 9
• B. 15
• C. 21
• D. 45

Q7. In a 3 × 3 magic square filled with the numbers 1 to 9, the number at the centre must be

• A. 1
• B. 9
• C. 5
• D. Any of 1 to 9

Q8. The first-ever recorded 4 × 4 magic square in India is called the Chautisa Yantra because its magic sum is

• A. 15
• B. 30
• C. 34
• D. 45

Q9. The first eight terms of the Virahanka-Fibonacci sequence are

• A. 1, 2, 3, 5, 8, 13, 21, 34
• B. 1, 1, 2, 3, 5, 8, 13, 21
• C. 2, 4, 6, 8, 10, 12, 14, 16
• D. 1, 3, 5, 7, 9, 11, 13, 15

Q10. In the Virahanka-Fibonacci sequence, the next number is obtained by

• A. Multiplying the previous two numbers.
• B. Adding the previous two numbers.
• C. Doubling the previous number.
• D. Subtracting the previous number from itself.

Q11. Which algebraic expression gives the nth even number?

• A. 2n
• B. 2n - 1
• C. n + 2
• D. n^2

Q12. Which algebraic expression gives the nth odd number?

• A. 2n
• B. n + 1
• C. n - 1
• D. 2n - 1

Q13. In this chapter, the word 'parity' is used to denote the property of being

• A. Even or odd.
• B. Positive or negative.
• C. Prime or composite.
• D. Rational or irrational.

Q14. The first magic square ever recorded, the Lo Shu Square, originated in

• A. Ancient India
• B. Ancient China
• C. Ancient Greece
• D. Ancient Egypt

Q15. In a cryptarithm such as T + T + T = UT, each letter stands for

• A. A particular digit from 0 to 9.
• B. A particular variable like in algebra.
• C. A unit such as metre or kilogram.
• D. A Roman numeral.