HELP GEOMETRY URGENT

Annika borrowed a book from the library and forgot to return it on time, the library charges .25 per day for the first four days

Delicious77 [7]

So work it out as 0.25x4 =£1
Then 4-1=£3
£3 / 0.30 =10
10+4
So it is 14 days late

6 0

3 years ago

The time needed to complete a final examination in a particular college course is normallydistributed with a mean of 80 minutes

Artist 52 [7]

Answer:

a) 0.023

b) 0.286

c) 10 students will be unable to complete the exam inthe allotted time.

Step-by-step explanation:

We are given the following information in the question:

Mean, μ = 80 minutes

Standard Deviation, σ = 10 minutes

We are given that the distribution of time to complete an exam is a bell shaped distribution that is a normal distribution.

Formula:

$z_{score} = \displaystyle\frac{x-\mu}{\sigma}$

a) P(completing the exam in one hour or less)

P(x < 60)

$P( x < 60) = P( z < \displaystyle\frac{60 - 80}{10}) = P(z < -2)$

Calculation the value from standard normal z table, we have,

$P(x < 60) =0.023= 2.3\%$

b) P(complete the exam in more than 60 minutes but less than 75 minutes)

$P(60 \leq x \leq 75) = P(\displaystyle\frac{60 - 80}{10} \leq z \leq \displaystyle\frac{75-80}{10}) = P(-2 \leq z \leq -0.5)\\\\= P(z \leq -0.5) - P(z < -2)\\= 0.309- 0.023 = 0.286= 28.6\%$

c) P(completing the exam in more than 90 minutes)

P(x > 90)

$P( x > 90) = P( z > \displaystyle\frac{90 -80}{10}) = P(z > 1)$

$= 1 - P(z \leq 1)$

Calculation the value from standard normal z table, we have,

$P(x > 90) = 1 - 0.8413 = 0.1587 = 15.87\%$

15.87% of children of class will require more than 90 minutes to complete the test.

Number of children =

$\dfrac{15.87}{100}\times 60 = 9.52\approx 10$

Approximately, 10 students of class will require more than 90 minutes to complete the test.

4 0

4 years ago

Martha bought new fish for her home aquarium. She Bought 3 guppies and 2 platies for a total of 13.95.Find the price of a guppy

Crazy boy [7]

Bought the same number of Guppies and only Hank bought 2 additional Platies. Thus, let’s subtract the total of Hank and Martha
=> 18.33 – 13. 95 = 4.38
Thus, Hank paid an additional of 4.34 for 2 platies. Let’s divide to get the price of platies
=> 4.34 / 2 = = 2.19 (price of platies each.)
Let’s solve for price of guppies
=> 13.95 – 4.34 = 9.61
=> 9.61 / 3 = 3.20 (Price of guppies each.)

8 0

3 years ago

Solve this equation: 2s + s + 12 = 132. <br> A. s = –30<br> B. s = 120<br> C. s = 9<br> D. s = 40

nataly862011 [7]

Solve your equation step-by-step.

2s+s+12=132

Simplify both sides of the equation.

2s+s+12=132

Simplify:

3s+12=132

Subtract 12 from both sides.

3s+12−12=132−12

3s=120

Divide both sides by 3.

3s/3 = 120/3

s=40

4 0

4 years ago

Read 2 more answers

A car and a truck left Washington, DC traveling in opposite directions. The car traveled 19 miles per hour faster than the truck

d1i1m1o1n [39]

Total speed was 1048 mi/(8 h) = 131 mi/h. The car was traveling at half this speed plus half the difference, (131 +19)/2 = 75 mi/h.

The truck was traveling at 75 mi/h -19 mi/h = 56 mi/h.

4 0

3 years ago