Answer:
30 ml of 45% salt solution and 20 ml of 30% salt solution.
Step-by-step explanation:
Let x be the amount of 45% salt solution and y be the amount of 30% salt solution
the two equation will be:
x+y=60 -- A
0.45x+0.3y=0.4(60) -- B
Solve by substitution
Rewrite Equation A
x+y=60
x=60-y --- C
Substitute C into B
0.45(60-y)+0.3y=24
27-0.45y+0.3y=24
-0.15y=-3
y=20
<u>Substitute</u> the y=20 into equation C
x=60-20
x=30
Therefore, there was 30 ml of 45% salt solution and 20 ml of 30% salt solution.
Since 7 - 3 is in parentheses, I will subtract that first, giving me 4. Next, I divide 11 and 4. 11 / 4 = 2.75
Answer:
2 50 mL bottles
Step-by-step explanation:
Find the cost per mL
55 / 80 mL =.6875 per mL
Now find the price of the buy one get one 1/2 off
45 + 1/2 (45) = 45+22.5=67.5
That will be for 50+50 mL
67.5 /100 ml =.675 per mL
The 100 mL is a better deal
Answer:
A
Step-by-step explanation:
This is because it is discounting however in the others it's increasing VAT=Value added Tax,
gain, 45-25=£20 profit therefore it's A.