Answer:
6 ounces
Step-by-step explanation:
Let x = the number of ounces of the 15% alcohol solution needed to be mixed with the 4 ounces of 20% alcohol solution to obtain the 17% alcohol solution.
After converting the percentages to their decimal equivalents, set up the necessary equation as follows:
0.15x+0.20(4) = (x+4)(0.17) Simplify and solve for x.
0.15x+0.8 = 0.17x+0.68 Subtract 0.15x from both sides.
0.8 = 0.02x+0.68 Now subtract 0.68 from both sides.
0.12 = 0.02x Finally, divide both sides by 0.02
x = 6
You need to mix 6 ounces of 15% alcohol solution with 4 ounces of 20% alcohol solution to obtain 10 (x+4)ounces of 17% alcohol solution.
9514 1404 393
Answer:
5/48, 5/46, 5/44, 5/42
Step-by-step explanation:
We can choose unit fractions with denominators between 8 and 10, separated by (10-8)/5 = 0.4 units:
1/8.4 = 5/42
1/8.8 = 5/44
1/9.2 = 5/46
1/9.6 = 5/48
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<em>Check</em>
- 1/8 = 0.125
- 5/42 ≈ 0.119
- 5/44 ≈ 0.114
- 5/46 ≈ 0.109
- 5/48 ≈ 0.104
- 1/10 = 0.100
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<em>Additional comment</em>
There are an infinite number of such fractions. We are given unit fractions with different denominators, so it works reasonably well to choose denominators between those given. Then the trick is to convert the fraction to a ratio of integers. In this case, multiplying by (5/5) does the trick.
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Another approach is to write the fractions with a common denominator, then choose numerators between the ones given. For example, 1/10 = 4/40, and 1/8 = 5/40, so you could write some fractions with numerators between 4 and 5. Possibilities are 4.1/40 = 41/400, 4.3/40 = 43/400, 4.7/40 = 47/400, 4.9/40 = 49/400.
The answer is
7.9306Using the formula in the attached:
Where: xi = sample value; μ = sample mean; n = sample size
1.) Calculate the mean first:
μ = 12.0 + 18.3 + 29.6 + 14.3 + 27.8 / 5
= 102 / 5
μ = 20.4
2.) Using the mean, calculate (xi - μ)² for each value:
(12.0 - 20.4)² = 70.56
(18.3 - 20.4)² = 4.41
(29.6 - 20.4)² = 84.64
(14.3 - 20.4)² = 37.21
(27.8 - 20.4)² = 54.76
3.) Sum the squared differences and divide by n - 1.
μ = 70.56 + 4.41 + 84.64 + 37.21 + 54.76
= 251.58 / 5-1
μ =
62.895 (this is now called sample variance)
4.) Get the square root of the sample variance:
√62.895 =
7.9306
Answer:
65+30x
Step-by-step explanation:
You forgot to give the choices.
But, I would think it's 65+30x=
Answer:
The answer is 8 quarters, 16 nickles, and 32 dimes
Step-by-step explanation:
- First, the equation would be (2/4d) x 5 +d x 10 +1/4d x 25= 600 (Don't put 6.00, that's dollars. We put 6 dollars into cents to make it easier.)
- Then we slowly start to solve: 10/4d + 10d + 25/4d = 600
- 10d+40d+25d/4 = 600 (Put all of that over 4, not first 25d)
- 75d= 600 x 4
- d=600 x 4/75 (same here put everything over 75)
- d=32
- So then n= 2 x 32/4 = 16
- Then n would be equal to : 1/4d= 1/4 x 32 = 8
- So your answer would be 8 quarters, 16 nickles, and 32 dimes.
Hope this helped :)