If the average (arithmetic mean) of 10 consecutive odd integers is 154, then the least of these integers is  Choose the correct choice from the following
A) a) 51 B) b) 58 C) c) 145 D) d)190 E) e)210
A very helpful rule to know in arithmetic is the rule that in evenly spaced sets, average = median. Because the average will equal the median in these sets, then we quickly know that the median of this set of consecutive odd integer numbers is 154.   There are 10 numbers in the set, and in a set with an even number of terms the median is just the average of the two most median terms (here the 5th and 6th numbers in the set). This means that numbers 5 and 6 in this set are 153 and 155. Because we know that number 5 is 153, we know that the smallest number is 4 odd numbers below this, which means that it is 4*2= 
<gadget id="calculator">4*2</gadget>
<output>8</output>
8 below this (every odd number is every other number). Therefore   153-8= 
<gadget id="calculator">  153-8</gadget>
<output>145</output>
145, answer choice c) 145
<result>C</result>
If the average (arithmetic mean) of 10 consecutive odd integers is 154, then the least of these integers is