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
15h + 80 = 140
If you wanted to solve how many hours he worked:
15h + 80 = 140
15h = 60
h = 4.
<span>1. </span><span>Given numbers
=> 7 centimeters convert to meters
In every 1 meter there are 100 centimeters
=> 7 / 100
=> 0.07
Therefore in 7 centimeters there are 0.07 meters.
7 cm is a whole number while 0.07 m is a decimal number
Scientific Notation of each numbers
=> 7 cm = 7 x 10^0
=> 7 m = 1 x 10^-2
Scientific notation by the way is an expression used by the scientist to make a
large number or very small number easy to handle.
</span>
The 3 inside angles of a triangle need to equal 180 degrees.
Add the 3 angles together to equal 180:
X + x+2 + 6x +10 = 180
Simplify:
8x + 12 = 180
Subtract 12 from each side:
8x = 168
Divide each side by 8:
x = 168 / 8
X = 21
a) x = 21
b) C = 6x+10
replace x with 21:
6(21) + 10 =
126 +10 = 136