issb mathematics MCQ #460

A alone 15 days, B alone 10 days. Together?

issb mathematics MCQ #460

  1. Question 1

    Q1. A alone 15 days, B alone 10 days. Together?

    • A) 5 days
    • B) 6 days
    • C) 7 days
    • D) 8 days

    Answer: 6 days

    Explanation: Rates 1/15 plus 1/10 equals 1/6 so 6 days together. Work each step carefully; ISSB math rewards accuracy under time pressure.