8.
The present age of A and B are in the ratio
of 8 : 7.27 years ago their age was in the
ratio 5:4. Find the age of elder one
Answers
Question:
The present age of A and B are in the ratio
of 8 : 7 . 27 years ago their age was in the
ratio 5:4 . Find the age of the elder one.
Answer:
72 years
Solution:
It is given that;
The present age of A and B are in the ratio
of 8 : 7.
Thus,
Let's assume that:
A's present age = 8x years
B's present age = 7x years
Also,
27 years ago ;
A's age = (8x - 27) years
B's age = (7x - 27) years
Now,
According to the question;
27 years ago their age was in the ratio 5:4 .
Thus;
=> (8x - 27):(7x - 27) = 5:4
=> (8x - 27)/(7x - 27) = 5/4
=> 4•(8x - 27) = 5•(7x - 27)
=> 32x - 4•27 = 35x - 5•27
=> 5•27 - 4•27 = 35x - 32x
=> 27•(5 - 4) = 3x
=> 27•1 = 3x
=> 3x = 27
=> x = 27/3
=> x = 9
Thus,
A's present age = 8x years
= 8•9 years
= 72 years
B's present age = 7x years
= 7•9 years
= 63 years
Clearly, here A is elder than B .
Hence,
The present age of elder one is 72 years .
Given :---
- Present age ratio = 8:7
- 27 years ago ratio = 5:4
- Find elder one age ..
Solution (1)
→ Let present age of A = 8x
→ Let Present age of B = 7x
Now,
→ Before 27 years A was = (8x-27)
→ Before 27 years B was = (7x-27)
According to Question Their Ratio was 5:4:,
so,
→ (8x-27):(7x-27) = 5:4
→ 4(8x-27) = 5(7x-27)
→ 32x -27*4 = 35x - 27*5
→ 35x-32x = 27(5-4)
→ 3x = 27
→ x = 9
So, A present age = 8x = 8*9 = 72 years.
and , B present age = 7x = 7*9 = 63 years .
Hence, Elder one is A and he is 72 years old ..
______________________________
Solution (2)
Shortcut Trick to Solve Question :
⋆ Present Age⠀⠀➞27 Yrs.⠀⋆ Before Age
Sona : Sonali⠀⠀⠀⠀⠀⠀⠀⠀⠀Sona : Sonali
⠀⠀8 : 7⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀5 : 4
◗ Difference of both Ratios is
(8 - 5) = and, (7 - 4) = 3,
so,
Divide Year Gap By that Number.
↦ Year Gap / Difference of Age
↦ 27 Years / 3
↦ 9
Now, Just Multiply the Outcome (9 in this Case) with any of the Ratio of find Age.
Here we have to Find Present Age :
◗ A = (8 × 9) = 72 Years
◗ B = (7 × 9) = 63 Years