Question

An ISU Computer Science shirt is sold in 6 colors, 5 sizes, striped or solid, and
long sleeve or short sleeve. (a) How many different shirts are being sold? (b) What if
the black and yellow shirts only come in short-sleeve and solid?

Answer 1

a)

$6\cdot5\cdot2\cdot2=120$

b)

$4\cdot5\cdot2\cdot2 +2\cdot5\cdot1\cdot1=80+10=90$