Answer:
Step-by-step explanation:
x = City Roast Colombian coffee
y = French Roast Colombian coffee
x + y = 20
Answer:
R = 3/50
Step-by-step explanation:
If you are trying to solve for a variable,
1. Simplify both sides of the equation:
3/4 - 5/6R = 7/10 will now be (-5/6r) + 3/4 = 7/10
2. Add -3/4 from both sides of the equation:
(-3/4) + 3/4 = 0 and (-3/4) - 7/10 = -1/20.
You will be left with: -5/6r = -1/20.
3. Divide both sides by (-5/6).
(-5/6r) / -5/6 = 1R or just R. (-1/20) / -5/6 = 3/50
You are left with the answer:
R = 3/50
<em>I hope this helps!</em>
$38.05 or more because you need a minimum of $38.10
Answer:
the answer is 8
Step-by-step explanation:
cube root of 512 is 8
Assume that the amount needed from the 5% solution is x and that the amount needed from the 65% solution is y.
We are given that, the final solution should be 42 ml, this means that:
x + y = 42 ...........> equation I
This can also be written as:
x = 42-y .......> equation II
We are also given that the final concentration should be 45%, this means that:
5% x + 65% y = 45% (x+y)
0.05x + 0.65y = 0.45(x+y)
We have x+y = 42 from equation I, therefore:
0.05x + 0.65y = 0.45(42)
0.05x + 0.65y = 18.9 .........> equation III
Substitute with equation II in equation III as follows:
0.05x + 0.65y = 18.9
0.05(42-y) + 0.65y = 18.9
2.1 - 0.05y + 0.65y = 18.9
0.6y = 18.9 - 2.1
0.6y = 16.8
y = 28 ml
Substitute with y in equation II to get x as follows:
x = 42-y
x = 42 - 28
x = 14 ml
Based on the above calculations:
amount of 5% solution = x = 14 ml
amount of 65% solution = y = 28 ml
The correct choice is:
The teacher will need 14 mL of the 5% solution and 28 mL of the 65% solution.
