Cement Mortar was being prepared by mixing cement to sand in the ratio of 1:6 by volume. In a cement mortar of 42 units of volume, how much more cement needs to be added to enrich the mortar to the ratio 2:9? Also explain the process.

total volume of cement mortar = 42 unit

ratio of cement to sand = 1 : 6

therefore the volume of cement = 42 / (1+6) = 42/7 = 6 units

the volume of sand = (42/7)*6 = 6*6 = 36 units

let x units cement need to be added to make the ratio 2:9.

therefore

thus 2 unit of cement must be added to make the ratio of volume of cement to the volume of sand as 2 : 9.

hope this helps you.

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