Question

If A : B = 3 : 5, B : C = 7 : 9 and C : D = 13 : 14 then A : D is equal to

Answer 1

Step-by-step explanation:

as 5a=3b

9b=7c

14c=13d

so 30a=18b=14c=13d

thus 30a=13d

hence a:d=13:30

Answer 2

Concept

Ratio is like a relationship between two quantities which are expressed in times of another quantity.

Given

A:B=3:5, B:C=7:9 and C:D=13:14

To find

A:D

Explanation

We have taken firstly A:B=3:5 and B:C=7:9, in this we have to take LCM of 5 and 7 which is 35 then we have to change these numbers into 35 which will be:

A:B=21:35   and B:C=35/45

In this way A:B:C=21:35:45.

C:D =13:14

Now we have to take LCM of 45 and 13 which is 585.

We have to change 45 and 13 into 495 so we will multiply accordingly.

A:B:C=273:455:585

C:D=585:630

Accordingly A:B:C:D=273:455:585:630.

Then A:D=273:630.

Hence the ratio between A and D will be 273:630.

#SPJ2