A library has an average of 510 visitors on Sunday and 240 on other days. The average number of visitors per day in a month of 30 days beginning with a Sunday is?  Choose the correct choice from the following choices:
A) 187  B) 279  C) 280  D) 285  E) 262
Since the month begins with a Sunday, so there will be five Sundays in the month.   Required average   = [(510 * 5) + (240 * 25)]/30 = 8550/30= 
<gadget id="calculator">8550/30</gadget>
<output>285</output>
285.   Answer:285
<result>D</result>
A library has an average of 510 visitors on Sunday and 240 on other days. The average number of visitors per day in a month of 30 days beginning with a Sunday is?