1)The following density function describes a random variable X. f(x) = (x/81) if 0

f(x)= (18-x)/81 if 9

a. Draw a graph of the density function and then use it to find the probabilities

below:

i. Find the probability that X lies between 1 and 8. ________

ii. Find the probability that X lies between 8 and 11. ________

iii. Find the probability that X is less than 10. ________

iv. Find the probability that X is greater than 7. ________

2)10. The following density function describes a random variable X. f(x) = 1 (x /2) if

0

a. Find the probability that X is greater than 1 ________

b. Find the probability that X is less than .5. _________

c. Find the probability that X is equal to 1.5. _________