Answer:
A batch of 20 semiconductor chips is inspected by choosing a sample of 3 chips. Assume 10 of the chips do not conform to customer requirements.
a) Number of different samples = 20C3 =
=1140
b) 2 good and one bad chip
Number of samples = 10C2 * 10C1 = 45 * 10 =450
c) 2 good 1 bad + 1 good 2 bad + 3 bad
Number of samples = 10C2 * 10C1 + 10C1 * 10C2 + 10C3
= 
I would say number 2 but dont take my word for it
9514 1404 393
Answer:
-135/14
Step-by-step explanation:
There are an infinite number of rational numbers between any pair of numbers you name. These two number have the decimal values ...
-67/7 = -9 4/7 = -9.571428... (repeating)
-78/8 = -9 3/4 = -9.75
So, numbers like -9.6 = -48/5, or -9.7 = -97/10 are rational numbers that lie in the range you specified.
If you like, you can convert these numbers to ones with a common denominator (56).
-67/7 = -536/56
-78/8 = -546/56
These limits suggest several possible rational numbers with 56 as a denominator: -540/56 = -135/14, for example.