+1768 A bag contains yellow, green, blue, and white marbles. The ratio of yellow, green, blue, white marbles is $4:1:2:3$. If the bag contains $20$ marbles, then how many blue marbles are there?
+60 If there are 20 marbles in the bag, and the ratio of marbles is 4:1:2:3
adding 4+1+2+3 = 10, which when multiplied by 2 results in 20, which means there are 4 blue marbles.
