Q4 of 15 Page 118

Amina Bibi has prepared masonry mixture with sand and cement in a ratio of measurement 7:1. But after the brick-work it is seen that 72 kg of mixture remains. She has added more cement with this mixture and the ratio of measurement of sand to cement becomes 6:1. Let’s work out the total quantity of cement she has mixed.


The ratio of mixture of sand and cement is 7:1,


This means total part of mixture is 8


Out of which 7 parts is sand and 1 part is cement,


Quantity of sand


= 7 × 9


= 63 kg


Quantity of cement


= 9 kg


72 kg of mixture is equal to 63 kg of sand and 9 kg of cement.


Let “x” kg cement is added,


Now ratio of sand to cement becomes 6:1.



⇒ 63 = 6(9 + x)


⇒ 63 = 54 + 6x


⇒ 63-54 = 6x


⇒ 9 = 6x


⇒ x = 1.5 kg


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