A van is delivering  180 bottles of drinks to a neighborhood, and each bottle contains either cider or beer or a mixture of two. Out of the  180 bottles, 40 contain only cider, 80 contain only beer, and the rest are a mixture of the two drinks. If the delivery man gives half the number of each bottle of drink to the first house, how many bottles does the first house get?
The total number of bottles containing cider or beer is 40+80 = 
<gadget id="calculator">40+80</gadget>
<output>120</output>
120.
If the number of bottles in the van was 180, then 180-120 =
<gadget id="calculator">180-120</gadget>
<output>60</output>
60 contains a mixture of the two drinks.
At the first house, the delivery man dropped 1/2*40 = 
<gadget id="calculator">1/2*40</gadget>
<output>20</output>
20 bottles.
There were also 1/2*80 = 
<gadget id="calculator">1/2*80</gadget>
<output>40</output>
40 bottles of beer that the delivery man gave to the first house.
Together, the first house received 40+20 = 
<gadget id="calculator">40+20</gadget>
<output>60</output>
60 bottles of cider and beer.
The total number of bottles that had a mixture of the two drinks that were dropped at the first house is 1/2*60 = 
<gadget id="calculator">1/2*60</gadget>
<output>30</output>
30.
The first house got 60+30 = 
<gadget id="calculator">60+30</gadget>
<output>90</output>
90 bottles of all types of drinks.

<result>90</result>