How much water must be added to 10 gallons of 10% brine solution to de

Question

How much water must be added to 10 gallons of 10% brine solution to decrease the concentration to 7%?

A. 0—1.5 gal
B. 1.5—3 gal
C. 3—4.5 gal
D. 4.5—6 gal
E. 6+ gal

Skywalker18 · Answer

Let amount of water that must be added in gallons to dilute concentration of brine solution = x
Amount of brine already present = 10/100 * 10 = 1 gallon
1/(10+x) *100 = 7
=>100 = 70 + 7x
=> x= 30/7 = 4.2

Answer C

SVISH · Answer

__________________________
let X be the amount of water to be added to the solution

0.1 (10) = 0.07( 10 + X)
X= 30/7 ; X = 4.2

Answer C

arjunperiyasamys · Answer

1+0 = 0.07 (10 + x )
1=0.7+0.07x
0.30=0.07x
 x=4.2

HENCE option c

Kudos if i helped

sowragu · Answer

Since 1 Gallon of brine is constant which constitutes 7%, How much will constitute 93%?

93/7 = 13.2

Approximately we need to add 4.2 Gallon of water. (13.2-9 = 4.2)

or the other way is

1 Gallon constitutes 7%. Hence 100% constitute

100/7 = 14.2. Hence 4.2 Gallon of water needs to be added.

APARNASHAH · Answer

let X be the amount of water to be added 0.1 (10) = 0.07( 10 + X) X= 30/7 ; X = 4.2 OA = C :-D

Wilfy · Answer

I've been doing a bunch of those "fruit has x% water" mixture questions, so I solved this a little differently. Can someone tell me if my logic is correct or if I got the right answer as a fluke?

Brine = 10% of 10L, Brine = 1L
1 = 7% of x, 1=(7/100)x
100/7=x
x= 14 (approx.)

So the final solution is a little more than 14 L, so answer is C.

law258 · Answer

Asking about H20 concentration:

0.90(10)+x=0.93(10+x)
9+x=0.3+0.93x
0.07x=0.3
x=30/7 = 4.2

C is the correct answer.

dorey777 · Answer

lawiniecke

instead 9+x=0.3+0.93x

it should be 9+x=9.3+0.93x

Typo error. So that no one gets confused.

bumpbot · Answer

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How much water must be added to 10 gallons of 10% brine solution to de

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