A bead pattern has orange to violet beads in the ratio 4:7. If there are 28 orange beads, how many violet beads are there?

الشرح

The orange term has been multiplied by 7 to change 4 into 28, so the violet term must also be multiplied by 7, giving 49. Adding the difference between 4 and 7 to 28 would not create an equivalent ratio.