1) choosing 3 of 5 toppings for pizza (you can have extra of something you like)

2) choosing 3 of 5 toppings for pizza ( you cannot order "doubles")

how many outcomes are possible? ?
this is compound probability.
do not understand at

1) Choosing 3 of 5 toppings for pizza (you CAN have extra of something you like)

meaning u can have the same toppings as ur 3 choices

so for each of the 3 choices, there are 5 options

total possible outcome = 5 x 5 x 5 = 125

2) Choosing 3 of 5 toppings for pizza ( you canNOT order "doubles")

meaning each choice can be selected just once

so after the first choice, there is only 4 options left; after 2nd, just 3

total possible outcome = 5 x 4 x 3 = 60