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:
88 comments Page 3 of 9.
Isaactamson said:
9 years ago
The 40% of 5 =2,
50% of 7 = 3.5,
75% of 8 = 6,
(5+2)x2 = 14,
(7+3.5)x2 = 21,
(8+6)x2 = 28,
= 16:21:28.
The ratio will be 2:3:4.
50% of 7 = 3.5,
75% of 8 = 6,
(5+2)x2 = 14,
(7+3.5)x2 = 21,
(8+6)x2 = 28,
= 16:21:28.
The ratio will be 2:3:4.
(2)
Harjinder Singh said:
1 decade ago
1. 40% of 5 = 2, total seats 5+2=7
2. 50% of 7 = 7/2 total seats 7+7/2=21/2
3. 75% of 8 = 6 total seats 8+6=14
now compare ratios of all 7:21/2:14=>14:21:28
=>2:3:4
2. 50% of 7 = 7/2 total seats 7+7/2=21/2
3. 75% of 8 = 6 total seats 8+6=14
now compare ratios of all 7:21/2:14=>14:21:28
=>2:3:4
(2)
Rahul said:
6 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)
Ahmad said:
8 years ago
Awesome, thanks @Ramesh.
(2)
Himesh said:
6 years ago
@All.
Would this formula be applicable if the number of seats is to be DECREASED rather than INCREASED?
And the ratios themselves are decreasing after solutions, how then the seats were increased? could anyone tell me why the ratios decreased instead of increasing?
Would this formula be applicable if the number of seats is to be DECREASED rather than INCREASED?
And the ratios themselves are decreasing after solutions, how then the seats were increased? could anyone tell me why the ratios decreased instead of increasing?
(1)
Sikander said:
9 years ago
Isn't that simple like if we add 40% + 50% + 70% = 165,
40/165 = 2.
50/165 = 3.
75/165 = 4.
40/165 = 2.
50/165 = 3.
75/165 = 4.
(1)
Faizan said:
1 decade ago
Previous ratio is 5:7:8, now by adding increase.
we get,
5+0.4*5 : 7+0.5*7 : 8+0.75*8 , which is 7:10.5:14.
Now it is simplified as 70:105:140 (by multiplying 10 with all).
And on simplifying by 7, we get new ratio as 2:3:4 .
we get,
5+0.4*5 : 7+0.5*7 : 8+0.75*8 , which is 7:10.5:14.
Now it is simplified as 70:105:140 (by multiplying 10 with all).
And on simplifying by 7, we get new ratio as 2:3:4 .
(1)
Pabitra said:
4 years ago
Still not clear.
Can you explain it clearly in a shortcut way?
Can you explain it clearly in a shortcut way?
(1)
Sonal mahajan said:
1 decade ago
Hi ramesh
Can you tell me please how it comes?
70: 105: 140 or
14: 21: 28 or
2: 3: 4
Can you tell me please how it comes?
70: 105: 140 or
14: 21: 28 or
2: 3: 4
(1)
Saina Dey said:
2 years ago
@Shiv.
/
Why we have to multiply 5, 7 and 8 with 140, 150 and 175? Can anyone explain it please?
/
Why we have to multiply 5, 7 and 8 with 140, 150 and 175? Can anyone explain it please?
(1)
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