An electronics store receives a shipment of 35 graphing calculators including 7 that are defective. Eight calculators are chosen at random to be sent to a local high school. 8. How many total selections can be m

Complete question :

An electronics store receives a shipment of 35 graphing calculators, including 7 that are defective. 8 of these calculators are selected for a local high school. (A) How many selections can be made? (B) How many of these selections will contain no defective calculators?

23535820 ways

3108105 ways

Step-by-step explanation:

A.) How many selections can be made:

Number of ways of selecting 8 calculators from 35

35C8 :

Combination formula :

nCr = n! /(n-r)! r!

35C8 = 35! / (35-8)!8!

35C8 = 35! / 27! 8!

35C8 = (35*34*33*32*31*30*29*28) / (8*7*6*5*4*3*2*1)

35C8 = 948964262400 / 40320

= 23535820 ways

B.) number of non-defective calculators :

35 - 7 = 28

28C8 = n! /(n-r)! r!

28C8 = 28! / (28-8)!8!

28C8 = 28! / 20! 8!

28C8 = (28*27*26*25*24*23*22*21) / (8*7*6*5*4*3*2*1)

28C8 = 2506375872000 / 40320

= 3108105 ways

i just took the test, the correct answer is .. 31.5 in.

im guessing (23,14). hope this : )