1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
solong [7]
3 years ago
12

Normal with a mean of 70 minutes and a standard deviation of 10 minutes. Using the 68-95-99.7 rule, what percentage of students

will complete the exam in under an hour?
Mathematics
1 answer:
lys-0071 [83]3 years ago
4 0
Note that 60=70-10\times1, i.e. a student that completes the exam in one hour falls exactly one standard deviation (in the negative direction) from the mean.

Now, you're looking for the proportion of students that fall below this, i.e. \mathbb P(Z. The empirical rule states that approximately 68% of a normal distribution falls within one standard deviation of the mean. That is,

\mathbb P(|Z|

This means that the proportion of students that fall outside this range is

\mathbb P(|Z|>1)=\mathbb P(Z1)=1-\mathbb P(|Z|

Because the distribution is symmetric, it follows that

\mathbb P(Z1)=\dfrac{0.32}2=0.16

This means the percentage of students that complete the exam in under an hour is 16%.
You might be interested in
Expanding logarithmic Expression In Exercise,Use the properties of logarithms to rewrite the expression as a sum,difference,or m
ch4aika [34]

Answer:

\ln x+\frac{1}{3}\ln (x^2+1)

Step-by-step explanation:

Consider the given expression is

\ln (x\sqrt[3]{x^2+1})

We need to rewrite the expression as a sum,difference,or multiple of logarithms.

\ln (x(x^2+1)^{\frac{1}{3}})        [\because \sqrt[n]{x}=x^{\frac{1}{n}}]

Using the properties of logarithm we get

\ln x+\ln (x^2+1)^{\frac{1}{3}}         [\because \ln (ab)=\ln a+\ln b]

\ln x+\frac{1}{3}\ln (x^2+1)        [\because \ln (a^b)=b\ln a]

Therefore, the simplified form of the given expression is \ln x+\frac{1}{3}\ln (x^2+1).

6 0
3 years ago
How much will a person pay for 11.6 pounds of bananas at a price of 1.51 per pound?
xz_007 [3.2K]

Answer:

17.52

Step-by-step explanation:

literally 11.6 x 1.51 and then round to hundredth place

3 0
3 years ago
Johnny has a job that pays $6 per hour plus tips. If Johnny worked 5 hours and made $45, write an equation in point-slope form t
stepladder [879]

Answer:

6*5=30

45-30=15

he made 15$ in tips.

6 0
4 years ago
(8.166×10^8)×(1.515×10^9)
loris [4]
The answer is ....1.237149 x 10^18
4 0
3 years ago
The volume of a 9 inch cube is?
Sedbober [7]
Answer:

A. 729 cu in

Explanation:

Step 1: 9x9 = 81
Step2: 81x9 = 729
8 0
3 years ago
Other questions:
  • ______To test the efficacy of vitamin C in preventing colds, army recruits are randomly assigned to one of two groups: one in wh
    15·2 answers
  • BRAINLIEST PLZ HELP A scatter plot with a line is shown below. Graph shows numbers from 0 to 10 at increments of 1 on the x axis
    14·2 answers
  • Colton swam once along the length of a pool that has a perimeter of 124 yd. The width of the pool is 20 yd. How many feet did Co
    8·2 answers
  • The side lengths of a triangle are 9, 12, and 15. Is this a right triangle?
    9·1 answer
  • Mr. Smith had 3/4 of a peach pie leftover. He split the leftover pie among his 3 co-workers.
    11·1 answer
  • What is the slope of the line
    14·1 answer
  • Help asap!! (i’ll give u brainliest)
    5·1 answer
  • 11 3/4 times 5 3/4 times 8
    10·2 answers
  • Do you remember how to graph rational numbers on a number line? Review with a Quick Check.
    7·2 answers
  • The question is 2pX3qX5r
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!