Aptitude - Problems on Ages - Discussion
Discussion Forum : Problems on Ages - General Questions (Q.No. 11)
11.
The present ages of three persons in proportions 4 : 7 : 9. Eight years ago, the sum of their ages was 56. Find their present ages (in years).
Answer: Option
Explanation:
Let their present ages be 4x, 7x and 9x years respectively.
Then, (4x - 8) + (7x - 8) + (9x - 8) = 56
20x = 80
x = 4.
Their present ages are 4x = 16 years, 7x = 28 years and 9x = 36 years respectively.
Discussion:
41 comments Page 2 of 5.
Jon said:
8 years ago
I didn't understand.
First of all, from where 80 came.
Secondly, how do we know that we must plus, 4x-8 and 7x-8 how come there is + in between. Isn't it 8 years ago. Then why plus?
Please, someone, explain in very simple manner.
First of all, from where 80 came.
Secondly, how do we know that we must plus, 4x-8 and 7x-8 how come there is + in between. Isn't it 8 years ago. Then why plus?
Please, someone, explain in very simple manner.
Pawan kumar said:
8 years ago
How to add 8?
Lavanya said:
9 years ago
8 years ago sum of their age is 56,
Present sum of their age is 80
Total parts of the ratio is 4+7+9 = 20
So, 80/20=4
4 * 4 ,7 * 4, 9 * 4 = 16, 28, 36.
Present sum of their age is 80
Total parts of the ratio is 4+7+9 = 20
So, 80/20=4
4 * 4 ,7 * 4, 9 * 4 = 16, 28, 36.
Ramya said:
9 years ago
It is simple method.
He has given present ages of persons mentioned that 8 years ago, then we can take as;
(4x - 8) + (7x - 8) + (9x - 8) = 56.
He has given present ages of persons mentioned that 8 years ago, then we can take as;
(4x - 8) + (7x - 8) + (9x - 8) = 56.
Karthika.l said:
10 years ago
Please explain in easy way?
Yunus said:
10 years ago
It is simple that eight years ago 56 and now 3 persons*8 years each = 24 years.
So 56+24 = 80 now we check options the sum of 80 is 16+28+36 = 80 is option B answer.
So 56+24 = 80 now we check options the sum of 80 is 16+28+36 = 80 is option B answer.
Ravi said:
1 decade ago
Why they minuses with 8?
Roshni said:
1 decade ago
It is a ratio of three values then why plus is coming?
Djdave said:
1 decade ago
f1:f2:f3 = 4:7:9.
f1 + f2 + f3 - 24 = 56.
f1 + f2 + f3 = 80.
f1 = 4 / 20 * 80 = 16.
f2 = 7/20 * 80 = 28.
f3 = 9/20 * 80 = 36.
f1 + f2 + f3 - 24 = 56.
f1 + f2 + f3 = 80.
f1 = 4 / 20 * 80 = 16.
f2 = 7/20 * 80 = 28.
f3 = 9/20 * 80 = 36.
Naveen kumar said:
1 decade ago
x(4+7+9) = 56+8+8+8.
Then we got x = 4.
For further answer each x term multiplied by 4.
Then we got x = 4.
For further answer each x term multiplied by 4.
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