Answer :
The sum of Peter, Richard, and John's ages is 191.
We know that the ratio of Peter's age to Richard's age is = 5/8 --(i)
The ratio of John's age to Peter's age is = 7/12 --(ii)
Similarly, the ratio of John's age to Richard's age is = (5*7)/(8*12)= 35/96 -(iii)
Using the value of (i),(ii),(iii), we get -
Age of Peter = (5*12)/(8*12) = 60/96
= 60 years of age
Age of John = (7*5)/(12*5) = 35/60
=35 years of age
From the value of (iii), since no one is over 100 years of age, the age of Richard= 96 years of age
Hence the sum of their ages is = 96+35+60
= 191
Therefore, we know that the sum of their ages is 191.
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