A alone can complete a work in 10 days, B alone can complete the same work in 20 days and C alone can complete the same work in 15 days. A and C work together for some time and left, If B worked for 10 days to complete the work, then A and C worked for how many days?
A alone can complete a work in 10 days, B alone can complete the same work in 20 days and C alone can complete the same work in 15 days. A and C work together for some time and left, If B worked for 10 days to complete the work, then A and C worked for how many days? Correct Answer 3 days
Given:
A alone can complete a work in 10 days.
B alone can complete the same work in 20 days.
C alone can complete the same work in 15 days.
Formula:
Total work = Efficiency × Time
Calculation:
Total work = 60 units (LCM of 10, 20 and 15)
Efficiency of A = 6 units/day
Efficiency of B = 3 units/day
Efficiency of C = 4 units/day
Let A and C worked for x, days
According to the question
(6 + 4) × x + 3 × 10 = 60
⇒ 10x = 60 – 30
⇒ 10x = 30
⇒ x = 30/10
⇒ x = 3 days
∴ A and C work for 3 days.
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Feb 20, 2025