Answer:
B) 100
Step-by-step explanation:
All 3 interior angles of a triangle add up to 180 so:
x + 25 + 55 = 180
x + 80 = 180
x = 180 - 80
x = 100
Answer:
6.28 or 157/25
Step-by-step explanation:
Firstly, you find the formula for the circumference of a circle which is C= PI ( diameter)
So since the radius is 1 you multiply it by 2 and get 2 so then you multiply 2 by 3.14 (pi) and get 6.28
I hope this helped!!!

Answer:
Step-by-step explanation:
From the information given:
mean life span of a brand of automobile = 35,000
standard deviation of a brand of automobile = 2250 miles.
the z-score that corresponds to each life span are as follows.
the standard z- score formula is:

For x = 34000


z = −0.4444
For x = 37000


z = 0.8889
For x = 3000


z = -2.222
From the above z- score that corresponds to their life span; it is glaring that the tire with the life span 30,000 miles has an unusually short life span.
For x = 30,500


z = -2
P(z) = P(-2)
Using excel function (=NORMDIST -2)
P(z) = 0.022750132
P(z) = 2.28th percentile
For x = 37250


z = 1
Using excel function (=NORMDIST 1)
P(z) = 0.841344746
P(z) = 84.14th percentile
For x = 35000


z = 0
Using excel function (=NORMDIST 0)
P(z) = 0.5
P(z) = 50th percentile