Multiple choice

. The ratio of the ages of A and B is 3:4. After 10 years, the ratio of their ages will be 4:5. What is the sum of their present ages?

  1. 60 years

  2. 70 years

  3. 80 years

  4. 50 years

  5. 90 years
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let ages be 3x and 4x. (3x+10)/(4x+10) = 4/5. 15x + 50 = 16x + 40. x = 10. Present ages are 30 and 40. Sum = 70.

AI explanation

Let the present ages of A and B be 3x and 4x years. After 10 years, the ratio of their ages is (3x + 10) / (4x + 10) = 4 / 5. Cross-multiplying gives 15x + 50 = 16x + 40, so x = 10. Their present ages are 30 and 40 years, and their sum is 70 years.

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