Aptitude - Problems on Ages - Discussion
Discussion Forum : Problems on Ages - General Questions (Q.No. 10)
10.
Sachin is younger than Rahul by 7 years. If their ages are in the respective ratio of 7 : 9, how old is Sachin?
Answer: Option
Explanation:
Let Rahul's age be x years.
Then, Sachin's age = (x - 7) years.
 |
x - 7 | = | 7 |
| x | 9 |
9x - 63 = 7x
2x = 63
x = 31.5
Hence, Sachin's age =(x - 7) = 24.5 years.
Discussion:
48 comments Page 1 of 5.
Mahesh Babu said:
8 years ago
Lets Sachin's age is x years.
And Rahul's age is y years,
Then x=y-7 because Sachin is younger than Rohit by 7 years it implies Sachin age is 7 years less Than Rohit,
In question, ages are in the 7:9.
So x/y=7/9,
9x=7y,
y=9x/7,
From the equation,
x=y-7.
substitute y=9x/7,
x=9x/7-7,
7x=9x-49,
2x=49,
So x=24.5.
So, Sachin's age =24.5 years.
And Rahul's age is y years,
Then x=y-7 because Sachin is younger than Rohit by 7 years it implies Sachin age is 7 years less Than Rohit,
In question, ages are in the 7:9.
So x/y=7/9,
9x=7y,
y=9x/7,
From the equation,
x=y-7.
substitute y=9x/7,
x=9x/7-7,
7x=9x-49,
2x=49,
So x=24.5.
So, Sachin's age =24.5 years.
(1)
Arun said:
1 decade ago
Ratio of their ages 7:9 ie, let the ratio of sachin & Rahul's present ages be 7x and 9x respectively and
As the question says Sachin is younger than Rahul by 7 yrs., we can write it as.,
9x = 7x + 7
2x = 7
x = 3.5
Therefore sachin's present age = 7x = 7*3.5 = 24.5 ans.
As the question says Sachin is younger than Rahul by 7 yrs., we can write it as.,
9x = 7x + 7
2x = 7
x = 3.5
Therefore sachin's present age = 7x = 7*3.5 = 24.5 ans.
Gowthami said:
1 decade ago
Present age of Rahul is x.
Sachin is 7 years older than Rahul so x+7.
Their ratio is 7:9.
x/x+7 = 7/9 cross multiplication is 9x = 7x+49.
9x-7x = 2x. So x = 49/2 = 24.1/2 = 24.5.
So this is my suggestion I hope you all are clear with that.
Sachin is 7 years older than Rahul so x+7.
Their ratio is 7:9.
x/x+7 = 7/9 cross multiplication is 9x = 7x+49.
9x-7x = 2x. So x = 49/2 = 24.1/2 = 24.5.
So this is my suggestion I hope you all are clear with that.
Vanita Sawant said:
1 decade ago
Hey guys i've another method 2 solve d same problem
Let Sachin's age be 'x' years
Therefore, Rahul's age will be x+7 years
x + 7 = 9
x 7
7(x+7)=9x
7x+49=9x
2x=49
x=24.5
Hence Sachin's is 24.5 years old
Let Sachin's age be 'x' years
Therefore, Rahul's age will be x+7 years
x + 7 = 9
x 7
7(x+7)=9x
7x+49=9x
2x=49
x=24.5
Hence Sachin's is 24.5 years old
Kannan said:
1 decade ago
How can the answer be a fraction, you all answered algebraically ; but age cannot be fraction na? if D is right option then Sachin and Rahul should have same date of birth to have the question true. If so answer should be E ?
Lakshmi said:
1 decade ago
Sachin : Rahul.
7 : 9.
x : x+7.
Just do cross mul then it becomes 7(x+7) = 9x.
7x+49 = 9x.
2x = 49.
x = 24.5.
7 : 9.
x : x+7.
Just do cross mul then it becomes 7(x+7) = 9x.
7x+49 = 9x.
2x = 49.
x = 24.5.
Karim mirazul said:
10 years ago
In question its said that Sachin is younger than Rahul.
So Sachin = x ages.
As per question, that means Rahul is 7 year elder than Sachin = x+7.
x/x+7 = 7/9.
9x = 7x+49.
2x = 49.
x = 24.5.
So Sachin = x ages.
As per question, that means Rahul is 7 year elder than Sachin = x+7.
x/x+7 = 7/9.
9x = 7x+49.
2x = 49.
x = 24.5.
PRABIR said:
1 decade ago
Friends.
Sachin is younger than Rahul 7 years.
Their ratio is 7:9.
Let Sachin = 7.
Rahul = 9.
Their difference = 2.
Now 2 is difference is 7.
1 is = 7/2 = 3.5.
Sachin is 7 = 7*3.5 = 24.5.
Sachin is younger than Rahul 7 years.
Their ratio is 7:9.
Let Sachin = 7.
Rahul = 9.
Their difference = 2.
Now 2 is difference is 7.
1 is = 7/2 = 3.5.
Sachin is 7 = 7*3.5 = 24.5.
Ahmedshaon said:
9 years ago
Let Sachin's age be x years.
Then, Rahul's age = (x + 7) years, As Sachin is 7 years less than Rahul.
x / x + 7 = 7 / 9,
9x = 7x + 49,
2x = 49,
x = 24.5.
Hence, Sachin's age = 24.5 years.
Then, Rahul's age = (x + 7) years, As Sachin is 7 years less than Rahul.
x / x + 7 = 7 / 9,
9x = 7x + 49,
2x = 49,
x = 24.5.
Hence, Sachin's age = 24.5 years.
(1)
Ramya devi said:
1 decade ago
Let us assume sachin's age be x and rahul's age be x+7, then.
x/x+7 = 7/9.
9x = 7(x+7).
9x = 7x+49.
9x-7x = 49.
2x = 49.
x = 49/2.
x = 24.5 This is the simplest and easiest to solve.
x/x+7 = 7/9.
9x = 7(x+7).
9x = 7x+49.
9x-7x = 49.
2x = 49.
x = 49/2.
x = 24.5 This is the simplest and easiest to solve.
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