The angles inside a trapezoid add up to equal 360 degrees
X = 360-90-90-75 = 105 degrees.
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.
Answer:
x=3
Step-by-step explanation:
It is pretty simple.
x = 3 means literally just a vertical line at +3 on the x-axis.
In contrast, y = 3 would mean a horizontal line at +3 on the y-axis.
If you would like to see this for yourself pull-up desmos on your browser and type it into the graphing calculator of desmos.
Using it's concept, the probabilities are given as follows:
a) C. 7/20.
b) D. 15/22.
<h3>What is a probability?</h3>
A probability is given by the <u>number of desired outcomes divided by the number of total outcomes</u>.
For item a, we have that there are 60 students with no curfew, and of those, 21 have no chores, hence the probability is given by:
p = 21/60 = 7/20
Which means that option C is correct.
For item b, we have that there are 66 students with no shores, and of those, 45 have a curfew, hence the probability is given by:
p = 45/66 = 15/22
Which means that option D is correct.
More can be learned about probabilities at brainly.com/question/14398287
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Answer:
g=12
Step-by-step explanation:
3 + g = 15
g = 15-3
g = 12
