D=event that chip selected is defective
d=event that chip selected is NOT defective
Four possible scenarios for the first two selections:
P(DDD)=15/100*14/99*13/98=13/4620
P(DdD)=15/100*85/99*14/98=17/924
P(dDD)=85/100*15/99*14/99=17/924
P(ddD)=85/100*84/99*15/98=17/154
Probability of third selection being defective is the sum of all cases,
P(XXD)=P(DDD)+P(DdD)+P(dDD)+P(ddD)
=3/20
Check the picture below.
doesn't that make it just a 20 x 14? well, surely you know what that area is.
Melissa will need 1.5 gallons of blue paint for each gallon of yellow paint.
I believe that when finding the radius of a circle you half the diameter, but when finding the circumference of a circle you need to multiply the diameter (14cm) by pi.
So 14xpi= 43.98229715
But it can be simplified/ rounded to 44cm.
Of course I might be incorrect so do please correct me if I am wrong.