Aptitude - Ratio and Proportion - Discussion
Discussion Forum : Ratio and Proportion - General Questions (Q.No. 4)
4.
Seats for Mathematics, Physics and Biology in a school are in the ratio 5 : 7 : 8. There is a proposal to increase these seats by 40%, 50% and 75% respectively. What will be the ratio of increased seats?
Answer: Option
Explanation:
Originally, let the number of seats for Mathematics, Physics and Biology be 5x, 7x and 8x respectively.
Number of increased seats are (140% of 5x), (150% of 7x) and (175% of 8x).
 |
 |
140 | x 5x |  |
, | |
150 | x 7x | |
and | |
175 | x 8x | |
| 100 | 100 | 100 |
| 7x, |
21x | and 14x. |
| 2 |
 The required ratio = 7x : |
21x | : 14x |
| 2 |
14x : 21x : 28x
2 : 3 : 4.
Discussion:
91 comments Page 3 of 10.
Hiitha said:
5 years ago
@All.
Still did not get clarified that why we should use 140/100?
Still did not get clarified that why we should use 140/100?
(3)
Insaan said:
5 years ago
@Ram Kundu.
7x : 21x/2 : 14x from 14x : 21x : 28
To make the same denominator we have to multiply with 2 (7x*2/2 and 14*2/2)
14x/2 : 21x/2 : 28x/2 ( now we have the same denominator) we can ignore the denominator
Take LCM of 14x: 21x: 28x,
We get 2x: 3x: 8x.
7x : 21x/2 : 14x from 14x : 21x : 28
To make the same denominator we have to multiply with 2 (7x*2/2 and 14*2/2)
14x/2 : 21x/2 : 28x/2 ( now we have the same denominator) we can ignore the denominator
Take LCM of 14x: 21x: 28x,
We get 2x: 3x: 8x.
(5)
Ram Kundu said:
5 years ago
How it become 14x : 21x : 28x? Please explain this step.
(9)
M Zubair said:
6 years ago
Excellent. Thanks all.
(3)
Shaik Babu said:
6 years ago
5 it is increased by 40%=5 * 40/100 = 2.
7 it is increased by50%=7 * 50/100 = 7/2.
8it is increased by 75%=8 * 75/100 = 6.
5+2=7/2+7 = 6 + 8.
7=21/2 = 14.
14=21 = 28.
2=3 = 4.
7 it is increased by50%=7 * 50/100 = 7/2.
8it is increased by 75%=8 * 75/100 = 6.
5+2=7/2+7 = 6 + 8.
7=21/2 = 14.
14=21 = 28.
2=3 = 4.
(62)
Udit said:
6 years ago
How 7x:21/2x:14x =14x:21x:28x?
Anyone, please explain to me.
Anyone, please explain to me.
Shiv said:
6 years ago
=>Maths : physics : Biology
=>. 5 : 7 : 8.
=> 5*140 : 7*150 : 8*175,
=>. 2 : 6 : 8.
=>. 5 : 7 : 8.
=> 5*140 : 7*150 : 8*175,
=>. 2 : 6 : 8.
(9)
Priya said:
7 years ago
Nice explanation Mr. Harjinder Singh. Way to think in a simple manner.
Rahul said:
7 years ago
Let the ratio 500:700:800.
Increase 200:350:600.
700:105:1400=14:21:28=2:3:4 answer.
Increase 200:350:600.
700:105:1400=14:21:28=2:3:4 answer.
(2)
Himanshu said:
7 years ago
5:7:8 means 5/20 which means 0.25.
2:3:4 means 2/9 which means 0.22.
But it is saying that the seats have increased. But according to maths the seats have decreased.
Can anyone please tell me how is this possible?
2:3:4 means 2/9 which means 0.22.
But it is saying that the seats have increased. But according to maths the seats have decreased.
Can anyone please tell me how is this possible?
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