Multiple choice

In 1998, A's age is equal to the product of the last two digits of his birth year. At the same time, B's age is 1.2 times the age of A. Find A's birth year and B's present age.

  1. 1958, 48 years

  2. 1985, 40 years

  3. 1973, 27 years

  4. 1978, 47 years

  5. Cannot be determined
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A Correct answer
Explanation

Let birth year be 1900 + 10x + y. Age in 1998 is 98 - (10x + y). Given 98 - 10x - y = x * y. 98 = 10x + y + xy. Add 10 to both sides: 108 = (x+1)(y+10). Testing values for x (digits 0-9), if x=5, 108 = 6 * (y+10) -> 18 = y+10 -> y=8. Birth year 1958. Age = 40. B's age = 1.2 * 40 = 48.

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