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Hi All,

I was trying to wade my way through the Free Quiz and I kinda got messed up when I reached Q#3.

I understand that when we remove R units from a mixture (of M units) and replace it with say R units of let's say the item B, and the process repeated N times

Then the ratio of A remaining to A originally present is given by

(1 - (R/M))^N

So in this scenario, Ratio of Water Left to Water originally present should be given by (1 - (1/15))^2 == (14/15)^2

So, The amount of milk present will be 150 - (14/15)^2

Is this the right approach??? or am I way off track??

Cheers,
-RK-

Hi ;
The approach is correct to the extent that the amount of water left is ((14/15)^2)*125*)*125 gallons of water in the original mixture. This is 108.89 gallons of water in the mixture of 150 gallons.

This is the required result.

Thanks.

Shaji.