A bag contains yellow, green, blue, and white marbles. The ratio of yellow, green, blue, and white marbles is 1:2:3:4. If the bag contains 180 marbles, then how many blue marbles are there?
+274 Assume:
the # of yellow marbles is x
the # of green marbles is 2x
the # of blue marbles is 3x
the # of white marbles is 4x
x+2x+3x+4x=180
10x = 180
x = 18
the # of blue marbles = 3x = 3(18) = 54 marbles
