Page 249 - ICSE Math 6

Self-Testing Exercise 1

NUMBER SYSTEM

1. Write all the 3-digit numbers formed by the digits 0, 5 and 9 without repetition of digits.
2. Write the greatest and the smallest 3-digit numbers divisible by 5.

3. Find the values of the following.

(a) 2,765 × 162 + 2,765 × 38 (b) 557 × 247 – 147 × 557
4. The product of two numbers is 288 and their HCF is 12. Find their LCM.
5. Find the greatest number that will divide 73, 128 and 228 leaving the remainder 3 in each case.

6. Find the least number which when divided by 20, 35 and 75 leaves the remainder 3 in each
case.
7. By how much does the sum of 4.892 and 13.423 exceed the sum of 4.96 and 11.450?

7 15
5
8. Arrange , and in ascending order.
9 27 6
5
1
9. Insert a fraction between and .
8 3
1
10. A sum of money is divided among three friends A, and C in such a way that A gets , B gets
1 and C gets the remaining money. If C gets ` 600, find the total sum of money. 4
3
11. Simplify.
(a) 6.25 × 3.48 + 12.60 – 2.25 (b) 14.3 – 1.57 + 10.09 – 5.45

12. Write the following sets in the roster form.
(a) The set A of consonants in the word VOWELS.

(b) The set X of all the integers between –2 and 2.
2
(c) P = {x | x = n , n ∈ W}
13. Write the following sets in the set-builder form.
(a) X = {1, 3, 5, 7, 9, 11, 13, 15} (b) P = {4, 8, 12, 16, …}

(c) A = {January, March, May, July, August, October, December}
14. Find the cardinal number of the following sets.

(a) A = {0} (b) X = φ
(c) B = {x | x is a day of the week} (d) P = {x | x ∈ N}

15. Classify the following sets as finite, infinite or null sets.
(a) X = {x | x is a prime number divisible by 4}

(b) A = {x | x is a multiple of 7, x ∈ N, x < 100}
2
(c) Y = {x | x = 0, x ∈ N}
(d) B = {…, –1, 0, 1, 2}

233