What to the nearest whole number of 0.9

Simplify the complex fraction

Irina-Kira [14]

Answer:

2 4/9

Step-by-step explanation:

You need to divide the two fractions.

You need to multiply 11/4 by the reciprocal of 9/8.

11/4 times 8/9

You can simplify first.

11 times 2/9

22/9

Simplify to

2 4/9

8 0

3 years ago

Read 2 more answers

A study of 420,076 cell phone users found that 131 of them developed cancer of the brain or nervous system. Prior to this study

Keith_Richards [23]

Answer:

a) 95% Confidence interval = (0.026%, 0.037%) to 3 d.p

b) The result of the 95% confidence interval does not agree with the previous rate of such cancer because the value 0.0224% does not lie within this confidence interval obtained.

Step-by-step explanation:

Confidence Interval for the population proportion is basically an interval of range of values where the true population proportion can be found with a certain level of confidence.

Mathematically,

Confidence Interval = (Sample proportion) ± (Margin of error)

Sample proportion = (131/420076) = 0.0003118483 = 0.0312%

Margin of Error is the width of the confidence interval about the mean.

It is given mathematically as,

Margin of Error = (Critical value) × (standard Error)

Critical value at 95% confidence interval for sample size of 420,076 is obtained from the z-tables because the sample size is large enough for the properties of the sample to approximate the population properties.

Critical value = 1.960 (from the z-tables)

Standard error = σₓ = √[p(1-p)/n]

n = sample size = 420,076

σₓ = √(0.0003118×0.999688/420076) = 0.0000272421 = 0.0000272

95% Confidence Interval = (Sample proportion) ± [(Critical value) × (standard Error)]

CI = 0.000312 ± (1.96 × 0.0000272)

CI = 0.000312 ± 0.0000534

95% CI = (0.0002586055, 0.0003653945)

95% Confidence interval = (0.000259, 0.000365)

95% Confidence interval = (0.0259%, 0.0365%) = (0.026%, 0.037%) to 3 d.p

b) The result of the 95% confidence interval does not agree with the previous rate of such cancer because the value 0.0224% does not lie within this confidence interval obtained.

Hope this Helps!!!

7 0

3 years ago

Dr. Blumen invested $5,000 part of it was invested in bonds at a rate of 6% in the rest was invested in a money market at the ra

abruzzese [7]

So... let's say the amounts invested were "a" at 6% and "b" at 7.5%.

ok.. hmm what's 6% of a? well, (6/100) * a or 0.06a.
what's 7.5% of b? well, (7.5/100) * b or 0.075b.

now... we know, whatever "a" and "b" are, they total the investment of 5000 bucks, thus a + b = 5000

and the interest yielded was 337.50, thus 0.06a + 0.075b = 337.50

thus $\bf \begin{cases}
a+b=5000\implies \boxed{b}=5000-a\\
0.06a+0.075b=337.50\\
----------\\
0.06a+0.075\left( \boxed{5000-a} \right)=337.50
\end{cases}$

solve for "a", to see how much was invested at 6%.

what about "b"? well, b = 5000 - a.

6 0

3 years ago

Read 2 more answers

How do you find the surface area

WITCHER [35]

Answer:

It depends on what shape you have. Here are some formulas for different shapes.

Step-by-step explanation:

Rectangular prism: 2lw + 2lh + 2wh

Cylinder: 2 pi r² + 2 pi rh

Sphere: 4 pi r²

Cone: pi r² + pi rl