Aptitude - Ratio and Proportion - Discussion
Discussion Forum : Ratio and Proportion - General Questions (Q.No. 6)
6.
The ratio of the number of boys and girls in a college is 7 : 8. If the percentage increase in the number of boys and girls be 20% and 10% respectively, what will be the new ratio?
Answer: Option
Explanation:
Originally, let the number of boys and girls in the college be 7x and 8x respectively.
Their increased number is (120% of 7x) and (110% of 8x).
 |
 |
120 | x 7x |  |
and | |
110 | x 8x | |
| 100 | 100 |
| |
42x | and | 44x |
| 5 | 5 |
 The required ratio = |
|
42x | : | 44x | |
= 21 : 22. |
| 5 | 5 |
Discussion:
61 comments Page 3 of 7.
Narayana Rao Gartam said:
1 decade ago
20% of 70 is 14 (20/100*70) So, Total increase is 84.
10% of 80 is 8 So, total increase is 88.
Ratio of 84/88 = 21/22,
i.e 21:22.
10% of 80 is 8 So, total increase is 88.
Ratio of 84/88 = 21/22,
i.e 21:22.
Prakash yadav said:
1 decade ago
20%of 7 = 1.4 : 10%of 8 = 0.8 .
7+1.4 : 8+0.8;
8.4 : 8.8;
84/10 : 88/10;
42/5 : 44/5;
21 : 22.
7+1.4 : 8+0.8;
8.4 : 8.8;
84/10 : 88/10;
42/5 : 44/5;
21 : 22.
Simran said:
1 decade ago
Can someone give short method?
Mateen said:
1 decade ago
How 120 and 110 come into the picture? Please explain sir.
Arvind_ap said:
1 decade ago
G, B.
7:8 = 70, 80.
20% 10% = 120, 110.
G = 70*120 = 840.
B = 80*110 = 880.
= 84/88 = 21/22.
Answer = 21:22.
7:8 = 70, 80.
20% 10% = 120, 110.
G = 70*120 = 840.
B = 80*110 = 880.
= 84/88 = 21/22.
Answer = 21:22.
Ankita said:
1 decade ago
Why we use decimal values instead of fraction value?
20% of 7 = 7/5.
10% of 8 = 4/5.
7/5:4/5 = 7:4.
So answer should be 7+7:4+8 = 14:12.
20% of 7 = 7/5.
10% of 8 = 4/5.
7/5:4/5 = 7:4.
So answer should be 7+7:4+8 = 14:12.
Aditya said:
1 decade ago
We also 7:8 is 70:80.
So 20% and 10% =120 and 110.
Then 70*120 = 840, 110*8 = 880.
Simply divide them, 840/880 = 21/22 (Answer).
So 20% and 10% =120 and 110.
Then 70*120 = 840, 110*8 = 880.
Simply divide them, 840/880 = 21/22 (Answer).
Hackersk said:
1 decade ago
How you took ratio 21:22 from 42/5:44/5?
How 5 is eliminated please explain?
How 5 is eliminated please explain?
Prakash said:
1 decade ago
Please tell me easy steps or tricks to find ratios in complex cases without working a lot of steps!
I m waiting! for your reply.
I m waiting! for your reply.
Swastik said:
9 years ago
Thanks @Priyabrata.
Your method is easy to solve the problem.
Your method is easy to solve the problem.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers