Page 94 - ICSE Math 4

Progress Worksheet

Mental Maths

1. Fill in the blanks.
(a) The largest factor of any number is ___________.

(b) ___________ is the smallest odd number.
(c) The mul ple of an ___________ number is always even.

(d) The greatest prime number less than 45 is ___________.
(e) ___________ is a factor of every number.

2. Write True or False.

(a) Every composite number can be wri en as a product of factors
that are prime numbers. _________

(b) A number is divisible by 3, if the sum of all its digits is divisible
by 3. _________
(c) If the smaller number in the given numbers is a factor of the
greater number, then the greater number will be the HCF of the
two numbers. _________

(d) 23 is a composite number. _________

Solve and Answer

3. Which of the following numbers are divisible by 9?
(a) 81 (b) 207 (c) 438 (d) 603 (e) 373

4. Find the H.C.F. of 36 and 45 by lis ng method.

5. Find the prime factors of the following numbers using the prime factoriza on
method.
(a) 56 (b) 72 (c) 68 (d) 81 (e) 26

6. List the fi rst fi ve common mul ples of the given numbers and then fi nd their
L.C.M.

(a) 7 and 4 (b) 9 and 6 (c) 2 and 7 (d) 3 and 5

7. Find the prime factors of the following numbers by factor tree method.
(a) 36 (b) 16

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