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?
2 : 3 : 4
6 : 7 : 8
6 : 8 : 9
None of these
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 6 of 9.

Bharadwaj said:   1 decade ago
Ramesh and Harjinder was explained well :).

Rupali said:   1 decade ago
HI sonal! ramesh divided 70,105,140 by 5 then answer will be 14:21:28 after that by 7 therefore answer is 2: 3: 4

Neelam said:   1 decade ago
As 5:7:8 totals to 20 so can we assume value say 2000 and can make proportion of value in the given ratio,and then can increase the value by the given percentage of 40,50 and 75,by doing this i m getting increased ratio as 2:3.5:6 can u please make me understand by this method.

RAHUL SINGH said:   1 decade ago
Let their Ratio be 5X,7X,8X. INCRISED %=140%,150%,175%
ATQ , 5X OF 140=7X,150%OF 7X=21/2X,175%OF 8X=12.

Their Ratio = 7X:21/2X:14X.

Taking LCM of Denominator, we get = 14:21:28=2:3:4

Satish said:   1 decade ago
Hi guys cool,

5:7:8

5*1.4 : 7*1.5 : 8*1.75

7 : 10.5 : 14

2 : 3 :4

Important NOTE : KEEP in fractions instead of decimals.

Gnaneswar said:   1 decade ago
Singh concept is correct.

Kushi said:   1 decade ago
Thanks harjinder.

Priyabrata said:   1 decade ago
Thanks Harjinder, Very easy method apply you.

Mk.raj said:   1 decade ago
Because% mean 100, than 40% increase means 140.

Sunita said:   1 decade ago
Very good and easy method singh. Keep it up.


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