Given f(x) = x^3 + kx – 15, and the remainder when f(x) is divided by x– 3 is -18, then what is the value of k?

Arestaurant offers a $12 dinner special that has 5 choices for an appetizer, 12 choices for an entrée, and 4 choices for a dessert. how many different meals are available when you select an appetizer, an entrée, and a dessert? a meal can be chosen in nothing ways. (type a whole number.)

Two customers went to a post office. first customer paid $12 for 14 and 5 envelopes the second paid 24.80 for 10 postcards and 15 envelopes. what is cost of each envelope?

Out of $20$ creepy-crawly creatures in a room, $80\%$ are flies and $20\%$ are spiders. if $s\%$ of the total legs belong to spiders, what is $s$?