The average age of three boys is 25 years and their ages are in proportion 3:5:7. What is the age in years of the eldest boy?
Choose the correct choice from the following options.
A) 6
B) 19
C) 35
D) 45
E) 51
3x + 5x + 7x = 75   x =5   7x =35   Answer:35
<result>C</result>
The average age of three boys is 25 years and their ages are in proportion 3:5:7. What is the age in years of the eldest boy?