Tough and Tricky questions: Word Problems.
A salesman's income consists of commission and base salary. His weekly income totals over the past 5 weeks have been $406, $413, $420, $436 and $395. What must his average (arithmetic mean) income over the next two weeks be to decrease his average weekly income to $400 over the 7-week period?	Choose the correct choice:	A) $350	B) $400	C) $365	D) $385	E) $375
OFFICIAL SOLUTION:   (C) First, we need to add up the wages over the past 5 weeks: $406 + $413 + $420 + $436 + $395 = $2070.   To average $400 over 7 weeks, the salesman would need to earn: $400 × 7 406 +  413 +  420 +  436 +  395= 
<gadget id="calculator">406 +  413 +  420 +  436 +  395</gadget>
<output>2_070</output>
$2070.   To average $400 over 7 weeks, the salesman would need to earn: $400 × 7= $2800.   Subtract $2070 from $2800 to determine how much he would need to earn, in total, over the next 2 weeks to average $400 for the 7 weeks: $2800 – $2070 = $730.   Dividing $730 by 2 will give us the amount he needs to earn on average over the next 2 weeks: $730/2= 
<gadget id="calculator">730/2</gadget>
<output>365</output>
$365.   The correct answer is choice ($365).
<result>C</result>
Tough and Tricky questions: Word Problems.
A salesman's income consists of commission and base salary. His weekly income totals over the past 5 weeks have been $406, $413, $420, $436 and $395. What must his average (arithmetic mean) income over the next two weeks be to decrease his average weekly income to $400 over the 7-week period?