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Divide the numerator and denominator by their gcd which is 5
Answer:
350 mL
Step-by-step explanation:
Let q represent the quantity (in mL) needed of the 70% solution. Then the total amount of mixture will be q+50 milliliters. The total amount of alcohol in the mixture will be ...
0.70q +0.30(50) = 0.65(50 +q)
.05q = 17.5 . . . . . . subtract (0.65q +1.50)
q = 350 . . . . . . . . . divide by 0.05
You will need 350 mL of the 70% solution.
x² - 80 = 0
Add 80
to each side: x² = 80
Square root
each side: x = √80
Look it up: x = + 8.944... (rounded)
and
x = - 8.944... (rounded).
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Here's a cleaner solution:
x² - 80 = 0
Add 80
to each side: x² = 80
Square root
each side: x = √80
But 80 = 16 · 5
So √80 = √16 · √5
√16 = 4, so x = 4 √5
Full question attached
Answer:
Paired t test
Explanation:
The paired sample t test is used to measure or compare the mean of two observations or samples by measuring each subject two times as is seen above with the gold measurement which would result in two sets or pair of samples in a statistical procedure. We observe from the question that we measure each gold with two methods and then compare result of the two methods in terms of their mean error using the paired t test.
