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\\October 8, 2025 12:13 PM Bharat Arora P-9 Reader _________________________ Date: ___________________74

Practice time 3d

1. State whether the following statements are 'true' or 'False'.
( a) A prime number has more than 2 factors.

( b) 1 is a composite number.

( c) 2 is the only even prime number.
( d) 97 is the greatest 2-digit prime number.

( e) 1 is the smallest prime number.

( f) 47 is a composite number.
2. Fill in the blanks.

( a) ______________ is the only prime number between 90 and 100.

( b) ______________ is the smallest and only even prime number.

( c) There are ______________ prime numbers between 1 and 100.

( d) The prime factors of 32 are ______________.

( e) _____________ is the smallest odd composite number.
3. Find the prime factors of the following numbers using the factor tree method.

( a) 18 (b) 28 (c) 32 (d) 40

( e) 64 (f) 90 (g) 78 (h) 120

4. Find the prime factors of the following numbers using the division method. draw
the factor tree for each.
( a) 27 (b) 48 (c) 54 (d) 63

( e) 78 (f) 91 (g) 65 (h) 96

( i) 8 (j) 112 (k) 125 (l) 144

HigHest common factor (Hcf) Think Tank Logical Thinking

Let us consider any two numbers, say 12 and 18. I am the biggest factor that
two or more numbers share.
List all the factors of 12 and 18. To find me, you list all the
factors and compare.
Factors of 12 are 1, 2, 3, 4, 6 and 12. I help you split things into the

Factors of 18 are 1, 2, 3, 6, 9 and 18. largest possible equal groups.
Common factors of 12 and 18 are 1, 2, 3 and 6. Who am I?

The highest common factor (HCF) of 12 and 18 is 6. FACTS
Thus, the highest common factor (HCF) of two or more numbers A common factor is a
number which is a factor
is the greatest number that divides each given number exactly. of two or more numbers.

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