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3 years ago

10

850 projects were entered in the science fair. If 86% of the projects did not receive a ribbon, then how many student projects d

id receive a ribbon?

1 answer:

Reptile [31]3 years ago

5 0

Answer:

731 of the projects received a ribbon.

Step-by-step explanation:

850 x 0.86 = 731

Hope this helps!

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Since the normal curve is not symmetrical the area corresponding to a z-score of +1.0 will be different from that corresponding

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What is the slope of a line that is parallel to the line y = 3/4 + 2?

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A study was conducted to measure the effectiveness of hypnotism in reducing pain. The measurements are centimeters on a pain sca

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The confidence interval for mean of the "before-after" differences is $\fbox{(-0.4037,1.8037)}$

Further explanation:

Find the difference between the before pain and the after pain.

Difference = before-after

Kindly refer to the Table for the difference of between the before and after pain.

Sum of difference = $5.6$

Total number of observation = $8$

Mean of difference = $0.7$

Sample standard deviation $s$ = $1.3201$

Level of significance = $5\%$

Formula for confidence interval = $\left( \bar{X} \pm t_{n-1, \frac{\alpha}{2}\%} \frac{s}{\sqrt{n}} \right)$

confidence interval = $\left( 0.7 \pm t_{8-1, \frac{5}{2}\%} \frac{1.3201}{\sqrt{8}} \right)$

confidence interval = $\left( 0.7 \pm t_{7, \frac{5}{2}\%} \frac{1.3201}{\sqrt{8}} \right)$

From the t-table.

The value of $t_{7, \frac{5}{2}\%$ = $2.365$

Confidence interval = $( 0.7 \pm 2.365}\times \frac{1.3201}{\sqrt{8}}) \right)$

Confidence interval = $\left( 0.7 - 2.365}\times \0.4667,0.7 + 2.365}\times \0.4667) \right$

Confidence interval = $(0.7-1.1037,0.7+1.1037)$

Confidence interval = $\fbox{(-0.4037,1.8037)}$

The $95\%$ confidence interval tells us about that $95\%$ chances of the true mean or population mean lies in the interval.

Yes, the hypnotism appear to be effective in reducing pain as confidence interval include includes the positive deviation from the mean.

Learn More:

1. Learn more about equation of circle brainly.com/question/1506955

2. Learn more about line segments brainly.com/question/909890

Answer Details:

Grade: College Statistics

Subject: Mathematics

Chapter: Confidence Interval

Keywords:

Probability, Statistics, Speed dating, Females rating, Confidence interval, t-test, Level of significance , Normal distribution, Central Limit Theorem, t-table, Population mean, Sample mean, Standard deviation, Symmetric, Variance.

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Tuition for one year at the community college Sean would like to attend is about $8,880. Sean plans to save money each month for

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First make an equation then solve for the variable.

8,800 is the end goal so that is what it is going to equal

Since his parents are contribuating 6,000 we can add that as a constant

Now it says in 2 years but it askes us in months so we times 2 by 12 to get 24 months he will be saving.

Now it is asking us how much he should save per month be we don't know that so that is our variable.

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Please help, i have been doing this for a while and it is still wrong.

adelina 88 [10]

Answer:

51.7661748226 degrees; 38.2338251774 degrees

Step-by-step explanation:

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tan(A) = 1.65/1.30

A = arctan(1.65/1.30)

A = 51.7661748226 deg

Looking at angle B, 1.65 m is ADJACENT and 1.30 m is OPPOSITE. Therefore, the equation is:

tan(B) = 1.30/1.65

B = arctan(1.30/1.65)

B = 38.2338251774 deg

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