The best way to do this is to draw a picture of ΔFKL and include line segment KM that is perpendicular to FL. This creates ΔFKM which is a 45°-45°-90° triangle and ΔLKM which is a 30°-60°-90° triangle.
Find the lengths of FM and ML. Then, FM + ML = FL
<u>FM</u>
ΔFKM (45°-45°-90°): FK is the hypotenuse so FM =
<u>ML</u>
ΔLKM (30°-60°-90°): from ΔFKM, we know that KM = , so KL =
<u>FM + ML = FL</u>
=
There is a typo error in the last part of the question. The corrected part is-
"If the probability that she orders just a grilled cheese sandwich is .76, what is the probability that she will order a grilled cheese or fries?"
Answer:
The probability that she will order a grilled cheese sandwich or fries is <u>0.43.</u>
Step-by-step explanation:
Given:
Probability of ordering fries is,
Probability of ordering cheese sandwich is,
Probability of ordering both sandwich and fries is,
Probability of ordering cheese sandwich or fries is given by the union of both the events 'F' and 'S' given as .
Now, using addition theorem of probability, we get:
Therefore, probability of ordering cheese sandwich or fries is 0.43.