Aptitude - Problems on H.C.F and L.C.M
Overview Exercise "Success has many fathers, while failure is an orphan."
- (Proverb)
21.
The greatest possible length which can be used to measure exactly the lengths 7 m, 3 m 85 cm, 12 m 95 cm is:
Answer: D
Explanation:
Required length = H.C.F. of 700 cm, 385 cm and 1295 cm = 35 cm.
22.
Three numbers which are co-prime to each other are such that the product of the first two is 551 and that of the last two is 1073. The sum of the three numbers is:
Answer: C
Explanation:
Since the numbers are co-prime, they contain only 1 as the common factor.
Also, the given two products have the middle number in common.
So, middle number = H.C.F. of 551 and 1073 = 29;
First number =
551
= 19; Third number =
1073
= 37.
29
29
23.
Find the highest common factor of 36 and 84.
Answer: E
Explanation:
36 = 22 x 32
84 = 22 x 3 x 7
2 x 3 = 12.
24.
Which of the following fraction is the largest ?
Answer: A
Explanation:
L.C.M. of 8, 16, 40 and 80 = 80.
7
=
70
;
13
=
65
;
31
=
62
8
80
16
80
40
80
Since,
70
>
65
>
63
>
62
, so
7
>
13
>
63
>
31
80
80
80
80
8
16
80
40
25.
The least number, which when divided by 12, 15, 20 and 54 leaves in each case a remainder of 8 is:
Answer: A
Explanation:
Required number = (L.C.M. of 12, 15, 20, 54) + 8
= 540 + 8
= 548.
Required sum = (19 + 29 + 37) = 85.