prat29 wrote:

Fresh dates contain 90% water while dry dates contain 28% water . How many kg of dry dates can be obtained from 36kg of fresh dates ?

A. 5Kg

B. 10Kg

C. 12 Kg

D. 6Kg

Responding to a pm:

Personally, I would use the method used by Bunuel above. But if you insist on using the "alligation method" which we call "scale method", here is how you can do it:

What two things are mixed to give the third?

Dry dates are mixed with water to give fresh dates.

Dry dates have 28% water, water is 100% water and fresh dates have 90% water.

Dry dates/water = w1/w2 = (A2 - Aavg)/(Aavg - A1) = (100 - 90)/(90 - 28) = 10/62 = 5/31

Mixing 5 kg of dry dates with 31 kg (to maintain consistency) of water will give you 36 kg of fresh dates.

Answer 5 kg

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