15% of 20 gal = 0.15 * 20 gal = 3 gal, so the solution contains 3 gal of salt.
If we add <em>x</em> gal of water to the solution, we end up with (20 + <em>x</em>) gal of solution. We want the new mixture to have a concentration of 10%, or
10% of (20 + <em>x</em>) gal = 0.1 * (20 + <em>x</em>) gal = 2 + 0.1<em>x</em> gal
of salt.
The amount of salt in the tank hasn't changed. Solve for <em>x </em>:
2 + 0.1<em>x</em> = 3
0.1<em>x</em> = 1
<em>x</em> = 10 gal
A) f(x)=0.2x
B)f(12)=0.2(12)=2.4 dollars
The solution to this problem is 5/2a^2b^5
Answer:
x=0,-1 and x=
x=\frac{2+\sqrt{10}}{3},\frac{2-\sqrt{10}}{3}x=
3
Step-by-step explanation:
1 Cancel 2 on both sides.
3{x}^{2}+3x=03x
2
+3x=0
2 Factor out the common term 3x3x.
3x(x+1)=03x(x+1)=0
3 Solve for xx.
x=0,-1x=0,−1
1 Move all terms to one side.
3{x}^{2}-3x-1-x-1=03x
2
−3x−1−x−1=0
2 Simplify 3{x}^{2}-3x-1-x-13x
2
−3x−1−x−1 to 3{x}^{2}-4x-23x
2
−4x−2.
3{x}^{2}-4x-2=03x
2
−4x−2=0
3 Use the Quadratic Formula.
x=\frac{4+2\sqrt{10}}{6},\frac{4-2\sqrt{10}}{6}x=
6
4+2√
10
,
6
4−2√
10
4 Simplify solutions.
x=\frac{2+\sqrt{10}}{3},\frac{2-\sqrt{10}}{3}x=
3
2+√
10
,
3
2−√
10
Total number of people on boat=30
Half as many children as adults means:
Number of children = 1/2 ( Adults)
Let number of adults= A
Then equation is:
So number of children= 1/2 x 20 =10
Answer: 10 Children