Final answer:
To find the number of unique people who have seen an Ali and Sophie show during this time period, we add up the percentages of fans who have come to different numbers of shows. The correct answer is 900 fans.
Step-by-step explanation:
To find the number of unique people who have seen an Ali and Sophie show during this time period, we need to add up the percentages of fans who have come to different numbers of shows. Let's calculate:
- 60% of fans have come once: 900 * 0.6 = 540 fans
- 30% of fans have come twice: 900 * 0.3 = 270 fans
- 6% of fans have come three times: 900 * 0.06 = 54 fans
- 4% of fans have come four times: 900 * 0.04 = 36 fans
To find the total number of unique people, we add up all the fans at different show frequencies: 540 + 270 + 54 + 36 = 900 fans.
Therefore, the correct answer is 900 (fans).