# 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 5*x*, 7*x* and 8*x* respectively.

Number of increased seats are (140% of 5*x*), (150% of 7*x*) and (175% of 8*x*).

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 |

14*x* : 21*x* : 28*x*

2 : 3 : 4.

Discussion:

84 comments Page 2 of 9.
Akash hotty said:
1 year ago

Can anyone explain it shortly?

(8)

Abdulsalam said:
2 years ago

How can we get the total number of seats?

Please, anyone, explain me.

Please, anyone, explain me.

(6)

Pabitra said:
3 years ago

Still not clear.

Can you explain it clearly in a shortcut way?

Can you explain it clearly in a shortcut way?

(1)

Hiitha said:
3 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:
3 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:
3 years ago

How it become 14x : 21x : 28x? Please explain this step.

(9)

M Zubair said:
3 years ago

Excellent. Thanks all.

(2)

Shaik Babu said:
4 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.

(60)

Udit said:
4 years ago

How 7x:21/2x:14x =14x:21x:28x?

Anyone, please explain to me.

Anyone, please explain to me.

Shiv said:
4 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.

(7)

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