Rachel has ribbons that are blue, green, red, orange, and yellow. To identify the plants in her garden, she ties either 1 ribbon, or 2 ribbons of different colors, to each plant. How many different plants can Rachel label in this way without labeling more than one plant the same way?	Choose the most appropriate option
A) 5 B) 10 C) 15 D) 20 E) 25
Number of plants identified by one color= 5.   Number of plants identified by a combination of 2 colors= 5152=105152=10   Total number = 5+10=15.5+10=15.	ANS:15
<result>C</result>
Rachel has ribbons that are blue, green, red, orange, and yellow. To identify the plants in her garden, she ties either 1 ribbon, or 2 ribbons of different colors, to each plant. How many different plants can Rachel label in this way without labeling more than one plant the same way?