The number of audience in a museum is 510 on Sunday and 240 on all other days. If the month is of 30 days and the first day of the month is Sunday, then what is the average number of audience in that month?

  Number of visitors on Sunday: 510   Number of visitors on other days: 240   Total number of days in the month: 30 Since the first day of the month is Sunday, there will be 5 Sundays in the month (including the first day). The remaining days (30 - 5 = 25) will have the number of visitors as 240. Now, we can calculate the total number of visitors for the month: Total visitors = (Number of Sundays × Visitors on Sunday) + (Number of other days × Visitors on other days)   = (5 × 510) + (25 × 240)     = 2550 + 6000   = 8550  Average number of visitors = Total visitors / Total days = 8550 / 30 = 285  So, the average number of audience in the museum for that month is 285.