My question is: Every 2 years, the number of swans at Rita's pond doubles. Currently, there are 15 swans in the pond. How many swans will there be in ten years? Your thoughts:
If currently there are 15 swans in the pond, in two years' time there will be 15 * 2 = 30 swans. In another two years, the number of swans in the pond will double to 2 * 30 = 60 swans. In another two years, the number of swans in the pond will double to 2 * 60 = 120 swans. If after 6 years there are 120 swans in the pond, in eight years times there will be 2 * 120 = 240 swans. In another two years, which is 10 years, there will be 2 * 240 = 480 swans in the pond. The final answer: 480.