10 x 4
2
10
= 5 x 2 x 2 x 2
40 = 8 * 5
= 2 * 2 * 2 * 5
5
1
40 = 2 x 2 x 2 x 5
Practice Set 11
O Factorise the following numbers into primes.
(i) 32
(11) 57
(111) 23
(y) 208
(vii) 765
(viii) 342
(IV) 150
(ix) 377
(v) 216
(x) 559
Let's recall.
Greatest Common Divisor (GCD) or Highest Common Factor (HCF)
We are familiar with the HCF and LCM of positive integers. Let us learn something mor
about them. The HCF or the GCD of given numbers is their greatest common divis
or factor
In each of the following examples, write all the factors of the numbers and find
greatest common divisor
(i) 28. 42 (ii) 51.27 (111) 25. 15, 35
Answers
Answer:
I. I. MEAN. YOU. NEED. THIS.
Step-by-step explanation:
Q1: If V means ‘divided by, – means ‘multiplied by’, V means ‘minus and V means ‘plus’, which of the following will be the value of the expression 16+ 8- 4 + 2 x 4? (Bank P.O. 1995)
(a) 16 (b) 28 (c) 32 (d) 44 (e) None of these
Q2: If + means +, – means x, + means + and x means then 36 x 12 + 4 + 6 + 2 – 3 = ?
(a) 2 (b) 18 (c) 42 (d) 6 (e) None of these
Q3: If A means ‘plus’, B means ‘minus’, C means ‘divided by’ and D means ‘multiplied by’, then 18 A 12 C 6 D 2 B 5 = ? (B.S.R.B. 1996)
(a) 15 (b) 25 (c) 27 (d) 45 (e) None of these
Q4: If x stands for + stands for +, + stands for + and – stands for x, which one of the following equations is correct? (S.S.C. 1999)
(a) 15 – 5 + 6 x 20 + 10 = 6 (b) 8 + 10 – 3 + 5 x 6 = 8 (c) 6 x 2 + 3 + 12 – 3 = 15 (d) 3 + 7 – 5 x 1 0 + 3 = 10
Q5: It being given that : > denotes +, < denotes -, + denotes +, – denotes =, = denotes less than’ and x denotes ‘greater than’, find which of the following is a correct statement.
(a) 3 + 2 > 4 < 9 + 3 < 2 (b) 3 > 2 > 4 = 18 + 3 < 1 (c) 3 > 2 < 4 x 8 + 4 < 2 (d)3 + 2 < 4 x 9 + 3 < 3
Q6: If x stands for ‘addition’, + stands for ‘subtraction’, + stands for ‘multiplication’ and – stands for ‘division’, then 20 x 8 + 8 – 4 + 2 – ? (Transmission Executives’ 1994)
(a) 80 (b) 25 (c) 24 (d) 5
Q7. If – means x, x means +, + means 4, and + means then 40x 12 + 3- 6 + 60 = ? (Bank P.O. 1993)
(a) 7.95 (b) 16 (c) 44 (d) 479.95 (e) None of these