What is the average (arithmetic mean) of all multiples of 10 from 10 to 100 inclusive?
Choose the correct choice from the following answers:
A) 190	B) 195	C) 200	D) 205	E) 55
This question can be solved with the Average Formula and 'bunching.'   We're asked for the average of all of the multiples of 10 from 10 to 100, inclusive.   To start, we can figure out the total number of terms rather easily:   1(10) = 10   2(10) = 20   ...   10(10) = 100   So we know that there are 10 total numbers.   We can now figure out the SUM of those numbers with 'bunching':   10 + 100= 
<gadget id="calculator">10 + 100</gadget>
<output>110</output>
110   20 + 90= 
<gadget id="calculator">20 + 90</gadget>
<output>110</output>
110   30 + 80= 
<gadget id="calculator">30 + 80</gadget>
<output>110</output>
110   Etc.   Since there are 10 total terms, this pattern will create 5 'pairs' of 110.   Thus, since the average= (Sum of terms)/(Number of terms), we have...   (5)(110)/(10) =55   Answer : 55
<result>E</result>
What is the average (arithmetic mean) of all multiples of 10 from 10 to 100 inclusive?