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
sasho [114]
3 years ago
8

The lengths of pregnancies are normally distributed with a mean of 269269 days and a standard deviation of 1515 days. a. Find th

e probability of a pregnancy lasting 309309 days or longer. b. If the length of pregnancy is in the lowest 44​%, then the baby is premature. Find the length that separates premature babies from those who are not premature.

Mathematics
1 answer:
kati45 [8]3 years ago
7 0

Answer:

a. 0.38%

b. 266.75 days

Step-by-step explanation:

We have the following data, mean (m) 269 and standard deviation (sd) 15, therefore:

a. The first thing is to calculate the number z:

z (x) = (x - m) / sd

z (309) = (309-269) / 15 = 2.67

When looking in the normal distribution table (attached), we have that at this value of z, the probability is:

P (z> 2.67), that is to say we must look in the table -2.67 and this value corresponds to 0.0038, that is to say 0.38%

b. Find the z-value with a left tail of 44%, i.e. 0.44. We look in the table for this value and what value of z corresponds.

invNorm (0.44) = -0.15

Find the corresponding number of days:

x = z * sd + m

we replace

d = -0.15 * 15 + 269 = 266.75 days

You might be interested in
Circumference of a circular disc is 157 cm, find its radius​
Zielflug [23.3K]

Answer:

Owwwww would be a good time

7 0
2 years ago
Read 2 more answers
Whoever gets it right can have brainliest but answer ASAP!
DaniilM [7]

Answer:

3 1/3

Step-by-step explanation:

Multiply

2 1/2 * 1 1/3 = 20/6

Simplify

20/6 = 10/3 = 3 1/3

4 0
2 years ago
Read 2 more answers
Solve<br> y=-x2-2x-2<br> y=x-4
Free_Kalibri [48]

Step-by-step explanation:

y−x2+2x=−4y-x2+2x=-4 , y+x=2

5 0
3 years ago
Question 7 options:<br><br> 2/3<br><br><br> 2<br><br><br> 8/27<br><br><br> 3
topjm [15]

Answer:

2/3

Step-by-step explanation:

If 2/3 · x= 4/9 then 4/9 ÷ 2/3= x

KCF (Keep Change Flip)

Keep 4/9

4/9 ÷ 2/3

Change from division to multiplication

4/9 · 2/3

Flip 2/3 to 3/2

4/9 · 3/2

Multiply 4 · 3= 12

Multiply 9 · 2= 18

Simplify

12 ÷ 6= 2

18 ÷ 6= 3

x=2/3

5 0
3 years ago
Helppppppppppppppppppppppppppppppppppppppppppppppppppppppppp
Anna [14]

Answer:

are you ok?

Step-by-step explanation:

why did you need help lol

5 0
3 years ago
Read 2 more answers
Other questions:
  • Suppose that 20% of the residents in a certain state support an increase in the property tax. An opinion poll will randomly samp
    9·2 answers
  • 63/84 in simplest form
    12·2 answers
  • Analyze the reflectional symmetry of the regular polygons. The square has -fold reflectional symmetry. The regular octagon has -
    15·1 answer
  • I. Let f(x) = 2x – 1, g(x) = 3x, and h(x) = x2<br> + 1. Compute the following:<br><br> 2. f o h(3)
    14·1 answer
  • Any one that knows this please help thanks!
    6·2 answers
  • I got a D+ on my maths test. The test was summative. Will it change my A to a D on my report card?​
    13·2 answers
  • Can you help me please?!
    6·1 answer
  • What is the value of x in simplest radical​ form?
    5·1 answer
  • Please help me worth 30 points!!
    10·1 answer
  • What is the probability of picking 1 orange shirt out of 8
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!