You have two boxes of colored pens. The first box contains a red pen, a blue pen, and green pen. The second box contains a yello
w pen, a red pen, and a black pen. What is the set that represents all the pens? A. {red pen, blue pen, green pen}
B. {red pen}
C. {red pen, red pen, green pen, yellow pen, black pen}
D. {red pen, blue pen, green pen, yellow pen, black pen}
I put 40 (Number of birthday cards bought previously) over 125 (Number of expected costumers) and multiplied it by 100 (Total number of card bought previously) to get my answer. Hopefully that helps :)