Let <em>q</em> be the number of quarts of pure antifreeze that needs to be added to get the desired solution.
8 quarts of 40% solution contains 0.40 × 8 = 3.2 quarts of antifreeze.
The new solution would have a total volume of 8 + <em>q</em> quarts, and it would contain a total amount of 3.2 + <em>q</em> quarts of antifreeze. You want to end up with a concentration of 60% antifreeze, which means
(3.2 + <em>q</em>) / (8 + <em>q</em>) = 0.60
Solve for <em>q</em> :
3.2 + <em>q</em> = 0.60 (8 + <em>q</em>)
3.2 + <em>q</em> = 4.8 + 0.6<em>q</em>
0.4<em>q</em> = 1.6
<em>q</em> = 4
Answer:
Its A.
Step-by-step explanation:
Can u stop reporting my answers!!??
scientist A dissolved 1 kg of salt in 3 litres.
scientist B dissolved 20 pounds of slat in 7 pint of water.
we know that 1 pound =0.543 g
20 pounds=9.07 kg.
1 pint=0.5 litres
so 7 pints =3.5 litres
so dissoving 1 kg of salt in 3 litres of water and 9.07 kg in 3.5 litres of water
we know that for concentration kg/l units is used .
for A= 1/3=0.33kg/l
and B=9.07/3.5=2.59 kg/l.
so scientist A has prepared more concentrated solution .