119. A contractor combined x tons of a gravel mixture that contained 10 percent gravel G, by weight, with y tons of a mixture that contained 2 percent gravel G, by weight, to produce z tons of a muxture that was 5 percent gravel G, by weight. What is the value of x?
1. y=10
2. z=16
Can someone help?
Mixtures question
This topic has expert replies
- outreach
- Legendary Member
- Posts: 748
- Joined: Sun Jan 31, 2010 7:54 am
- Thanked: 46 times
- Followed by:3 members
option Dtahitiboy wrote:119. A contractor combined x tons of a gravel mixture that contained 10 percent gravel G, by weight, with y tons of a mixture that contained 2 percent gravel G, by weight, to produce z tons of a muxture that was 5 percent gravel G, by weight. What is the value of x?
1. y=10
2. z=16
Can someone help?
we know that
x + y =z - (1)
also we know that gravel G
.1x+.02y=0.05z - (2)
from option 1
if we substitute y value in eq 1 and eq 2, we will two equations with x and z unknown variables. Solve the 2 eq to get the answer
from option 2
if we substitute z value in eq 1 and eq 2, we will two equations with x and y unknown variables. Solve the 2 eq to get the answer
Last edited by outreach on Thu Apr 08, 2010 10:47 pm, edited 1 time in total.
-------------------------------------
--------------------------------------
General blog
https://amarnaik.wordpress.com
MBA blog
https://amarrnaik.blocked/
--------------------------------------
General blog
https://amarnaik.wordpress.com
MBA blog
https://amarrnaik.blocked/
- thephoenix
- Legendary Member
- Posts: 1560
- Joined: Tue Nov 17, 2009 2:38 am
- Thanked: 137 times
- Followed by:5 members
eqn is 0.1x+0.02y=0.05z
in order to get x we need bth y and z
hence C
a big mistake i forgot x+y=z
so Now D is the ans
in order to get x we need bth y and z
hence C
a big mistake i forgot x+y=z
so Now D is the ans
- eaakbari
- Master | Next Rank: 500 Posts
- Posts: 435
- Joined: Mon Mar 15, 2010 6:15 am
- Thanked: 32 times
- Followed by:1 members
Ill tell you a neat trick to approach all mixtures questions.
Just remember the formula
% of higher-% of mean :% of mean - %of lower :: lower weight : higher weight
Stem:
Here our higher is x tons of 10%G
lower is y tons of 2%G
mean is z tons of 5%G
Substitute
5:3 :: y: x
Statement 1 gives us y , we can easily find x
Statement 2 gives us z which is x + y we can easily find x
Hence D
Just remember the formula
% of higher-% of mean :% of mean - %of lower :: lower weight : higher weight
Stem:
Here our higher is x tons of 10%G
lower is y tons of 2%G
mean is z tons of 5%G
Substitute
5:3 :: y: x
Statement 1 gives us y , we can easily find x
Statement 2 gives us z which is x + y we can easily find x
Hence D
Whether you think you can or can't, you're right.
- Henry Ford
- Henry Ford