Answer:
6
Step-by-step explanation:
30% of 20 = 30% * 20
= 
* 20
= 6
Answer:
-4 +4 =0
Step-by-step explanation:
The sum of a number and its' additive inverse is 0
The additive inverse of -4 is 4
-4 +4 =0
Suppose x grams of 8% solution should be mixed to make 100 g of 3% solution.
here we shall have:
the amount of 3% solution in the 100 g will be:
3/100*100=3 grams
the the equation will be, 8% of what quantity becomes 3g?
(8/100)*x=3
hence solving for x we shall have:
0.08x=3
x=3/0.08
x= 37.8 grams
The implication of this is that, when you have 37.5 grams of 8% solution, that will contain 3 of pure chemical and hence when you add more solvent on top of 37.5 g until you reach 100g, that will be 3% solution.
