A person's present age is two-fifth of the age of his mother. After 8 years, he will be one-half of the age of his mother. How old is the mother at present?
বিকল্পসমূহ (নিজের উত্তর যাচাই করতে ক্লিক করুন):
সঠিক উত্তর
1 (40 years)
বিস্তারিত ব্যাখ্যা ও বিশ্লেষণ:
Solution:
Let the mother's present age be x years.
Then, the person’s present age = (2/5)x years.
According to the question:
After 8 years:
(2x/5) + 8 = (1/2)(x + 8)
Multiply both sides to eliminate fractions:
(2x + 40) / 5 = (x + 8) / 2
⇒ 2(2x + 40) = 5(x + 8)
⇒ 4x + 80 = 5x + 40
⇒ 80 - 40 = 5x - 4x
⇒ x = 40
✅ Mother’s present age = 40 years
