Multiple choice

If 25 pumps can raise 2500 tonnes of water in 20 days, working 5 hours a day; in how many days will 20 pumps raise 1200 tonnes of water, working 8 hours a day?

  1. 6 days

  2. 3/2 days

  3. 15/2 days

  4. 7/2 days
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Use the formula (M1 * D1 * H1) / W1 = (M2 * D2 * H2) / W2. (25 * 20 * 5) / 2500 = (20 * D2 * 8) / 1200. 2500 / 2500 = 1 = (160 * D2) / 1200. D2 = 1200 / 160 = 120 / 16 = 7.5 = 15/2.

AI explanation

Using the formula (P1 times D1 times H1) divided by W1 equals (P2 times D2 times H2) divided by W2, we substitute the given values to find the unknown number of days. This gives (25 times 20 times 5) divided by 2500 equals (20 times D2 times 8) divided by 1200. Solving the equation 1 equals (160 times D2) divided by 1200 yields D2 equals 15 divided by 2 days.

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