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
<span>215,212,736
Round by 10,000 is 215,210,000</span>
So we start off with what 4 numbers added together equal 32.
first truck 5 tons
second truck 7 tons
third truck 9 tons
and fourth truck 11.
5+7= 12 +9 = 21+11= 32.
Answer:
the answer would be a because 42÷6=7 and 42÷3=14.
