Answer:
144°
Step-by-step explanation:
step 1
Find the measure of the central angle of the regular pentagon
Divide 360 degrees by 5 (the number of sides)
Let
c----> the center of the pentagon
we know that
m∠ECA=72°
m∠ACB=72°
therefore
m∠ECB=m∠ECA+m∠ACB
substitute the values
m∠ECB=72°+72°=144°
The measure of angle ECB is equal to the degrees that the pentagon rotate
Step-by-step explanation:
Since, y varies inversely as x.
Answer:
There are a 25% probability that Christine fails the course.
Step-by-step explanation:
We have these following probabilities:
A 50% probability that Christine finds a tutor.
With a tutor, she has a 10% probability of failling.
A 50% probability that Christine does not find a tutor.
Without a tutor, she has a 40% probability of failing.
Probability that she fails:
10% of 50%(fail with a tutor) plus 40% of 50%(fail without a tutor). So
There are a 25% probability that Christine fails the course.