John is a door-to-door salesman.  He visits 50 houses a day.  20% of them buy something from them.  Of those that buy something half buy a $50 set of knives and the other half buy a $150 set of knives.  How much does he sell a week when he works 5 days a week?
There are 50*.2=
<gadget id="calculator">50*.2</gadget>
<output>10</output>
10 houses buying from him per day.
Of those 10/2=
<gadget id="calculator">10/2</gadget>
<output>5</output>
5 buy each type of knife set.
So he gets 5*50=$
<gadget id="calculator">5*50</gadget>
<output>250</output>
250 per day from the cheap set.
He also gets 5*150=$
<gadget id="calculator">5*150</gadget>
<output>750</output>
750 from the expensive set.
So he makes a total of 250+750=$
<gadget id="calculator">250+750</gadget>
<output>1_000</output>
1000 per day.
That means he makes 1000*5=$
<gadget id="calculator">1000*5</gadget>
<output>5_000</output>
5000.

<result>5_000</result>