Two brothers were talking about how the older they get, the less

Question

Two brothers were talking about how the older they get, the less significant the difference in their ages seems to be. Specifically, they noticed that, 20 years ago, the ratio of their ages (in years) was 1:2; now, the ratio is 5:6; and, 20 years from now, the ratio will be 9:10.

Based on the information provided, select for Difference in ages the difference, in years, in their ages, and select for Sum of ages now the sum, in years, of their ages now. Make only two selections, one in each column.

Apt0810 · Accepted Answer

Current age of A = 5x
Current age of B = 6x

Now ratio of their ages 20 years ago = 5x-20/6x-20 =1/2 so from this x=5,so the current age of A =25 and that of B=30. And the ratio of their ages 20 years from now will be 9:10

Now per the question Difference in their ages= 5
 And sum = 30+25= 55

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gvij2017 · Answer

Ans: 
Difference in age: 5
Sum of age: 25+30=55

I have one more thought for this problem.

Current age is x and y respectively. 
x/y = 5/6

x-y/x+y= -1/11 (Here we are talking about absolute value of difference. so consider the ration 1/11)

So sum must be multiple of 11 and then you can figure out the difference in age.

SaurabhPatil20 · Answer

assume that 2 persons as a and b:
a-20/b-20 = 1/2 ........(1)
a/b = 5/6 .........(2)
a+20/b+20 .........(3)

using equation 2:  6a = 5b 
but those values in equation 1 :
2a-40 = b-20
2a - b = 20........(Multiply this equation by 3)
6a - 3b = 60 (Now Put  6a = 5b as given above) 
5b - 3b = 60
2b=60 
b=30 
Now Put b=30 in equation (2) so a = 25

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Two brothers were talking about how the older they get, the less

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