Mary bought a packet of 1500 stickers. She shared them between Susan, Andrew and Sam in the ratio 1:1:3 respectively. If Sam gave Andrew two-thirds of his own share, how many stickers does Andrew now have? Think carefully first, then make a decision:
The sum of the ratio is 1 + 1 + 3 = 5, therefore each part is 1500 / 5 = 300 stickers. Sam got 3 parts for a total of 3 * 300 = 900 stickers. He gave two - thirds of this which is 900 * (2 / 3) = 600 stickers to Andrew. Andrew had one part already, which is 1 * 300 = 300. Andrew now has a total of 300 + 600 = 900 stickers. So, the answer is 900.