Wednesday

April 1, 2015

April 1, 2015

Posted by **Kyle** on Thursday, August 25, 2011 at 3:10pm.

He has 700 kg of a cement mix that is 80% sand and 20% cement.

How much cement should he add so that he gets the required mix?

My set up:

required mix = (S)(.7) + (C)(3)

700kg = (S)(.8) + (C+X)(.2)

Is this even correct?

- Math -
**Henry**, Thursday, August 25, 2011 at 4:27pmC / (S+c) = 0.3.

C = 0.8 * 700kg = 560kg.

C / (560+C) = 0.3,

C = 168 + .3C,

C - 0.3C = 168,

0.7C = 168,

C = 240kg.

**Answer this Question**

**Related Questions**

Math - Mr Kim mix cement and sand to make a mixture.He uses 2 pails of cement ...

Algebra 1 - You are making up your own mix of concrete to patch a set of stairs...

Math,Ratio - mr kim mixes cement&sand to make a mixture.he uses 2 pails of ...

Maths - Sam used cement and sand to prepare a mixture. The ratio of the number ...

Math - A contractor has been asked to pave 15 miles of new road. Before he can ...

math((PLEASE HELP!)) - A contractor has been asked to pave 15 miles of new road...

Algebra - A batch of concrete is made by mixing 1 part cement, 2.5 parts sand, ...

algebra - elmer burns works for a ready-mix concrete cmpany. elmer receives an ...

geometry - Find the weight to the nearest kg, of the cement block. Cement weighs...

5th grade math - bill is replacing the grass in his yard with cement .the yard ...