The ratio of the ages of two friends is 7 : 9. After 10 years, it will be 19 : 23. What will be the average age after 7 years from now?
Answer & explanation
Correct answer: option 4
ATQ,
Let ages of two friends be 7x and 9x
After 10 years \(\frac{7x + 10}{9x + 10}\) = \(\frac{19}{23}\)
⇒ 161x + 230 = 171x + 190
⇒ 10x = 40
x = 4
After 7 years their ages will be 35 and 43
Average of age after 7 years = 39 years