19
Q:

# The least number which when divided by 5, 6 , 7 and 8 leaves a remainder 3, but when divided by 9 leaves no remainder, is:

 A) 1677 B) 1683 C) 2523 D) 3363

Explanation:

L.C.M. of 5, 6, 7, 8 = 840.

Required number is of the form 840k + 3

Least value of k for which (840k + 3) is divisible by 9 is k = 2.

Required number = (840 x 2 + 3) = 1683.

Q:

Find the least common multiple of 15 and 12?

 A) 3 B) 12 C) 30 D) 60

Explanation:

The least common multiple of 12 and 15 is

12 = 2 x 2 x 3

15 = 3 x 5

LCM of 12 and 15 is  2 x 2 x 3 x 5 = 60.

3 315
Q:

The G.C.D of 1.08, 0.36 and 0.9 is

 A) 0.9 B) 0.36 C) 0.18 D) 1.08

Explanation:

G.C.D is nothing but H.C.F

Given numbers are 1.08 , 0.36 and 0.90

we can take as 108, 36 and 90

Then required H.C.F is 18.

Therefore, H.C.F of given numbers is 0.18.

4 474
Q:

H.C.F of 3240, 3600 and a third number is 36 and their L.C.M is

 A) 47628 B) 49874 C) 24157 D) 42146

Explanation: 6 1122
Q:

Find the lowest common multiple of 24, 36 and 40?

 A) 360 B) 420 C) 240 D) 120

Explanation:

To find the LCM of 24, 36 and 40

24 = 2 x 2 x 2 x 3

36 = 2 x 2 x 3 x 3

40 = 2 x 2 x 2 x 5

Now, LCM of 24, 36 and 40 = 2 x 2 x 2 x 3 x 3 x 5

= 8 x 9 x 5

= 72 x 5

= 360

6 528
Q:

Three different containers contain 1365 litres, 1560 litres and 1755 litres of mixtures of milk and water respectively. What biggest measure that can measure all the different quantities exactly ?

 A) 37 lit B) 97 lit C) 129 lit D) 195 lit

Explanation:

From the given data,

containers contain mixtures of milk and water as 1365 lit, 1560 lit and 1755 lit.

Biggest measure that can measure all these different quantities exactly can be given by

HCF of (1365, 1560, 1755)

That can be found as

HCF of 1365, 1755 = 195

Now, HCF of 195 and 1560 = 195

Hence, biggest measure that can measure all the given different quantities exactly is 195 lit.

5 643
Q:

What is a Common Multiple?

If the Multiples for two or more numbers which are Common, then those Multiples are said to be Common Multiples.

For Example :

Multiples of 3 are 3, 6, 9, 12, 15, 18, 21, 24, 27, 30,...

Multiples of 5 are 5, 10, 15, 20, 25, 30,...

Here common multiples of 3 & 5 upto 30 are 15, 30.

1540
Q:

LCD of 12 and 18

 A) 36 B) 42 C) 12 D) 6

Explanation:

LCD is nothing but Lowest or Least Common Denominator

Here LCD of 12 and 18 means LCD of two fractions with denominators 12 and 18 respectively.

Therefore, LCM of 12 & 18 = 6 x 3 x 2 = 36

•  How to calculate LCD ::

The lowest common denominator or least common denominator (LCD) is the least common multiple (LCM) of the denominators of a set of fractions.

18 2782
Q:

54, 60  LCM is

 A) 600 B) 540 C) 60 D) 54

Explanation:

Here the LCM of 54, 60 is

=> 2 x 3 x 3 x 3 x 10

= 6 x 9 x 10

= 54 x 10

540.