Salaria is growing oranges this summer. She bought two types of trees. She has 50% of tree A and 50% of tree B. Tree A gives her 10 oranges a month and 60% are good. Tree B gives her 15 oranges and 1/3 are good. If she gets 55 good oranges per month, how many total trees does she have?
Each tree A gives her six good oranges a month 10 x .6 = 
<gadget id="calculator">10*.6</gadget>
<output>6</output>
6.
Each tree B gives her five good oranges a month because 15 x (1/3) = 
<gadget id="calculator">15*(1/3)</gadget>
<output>5</output>
5.
On average, a tree gives her 5.5 oranges a month because .5(6) + .5(5) = 5.5.
She has ten total trees because 55 / 5.5 = 
<gadget id="calculator">55/5.5</gadget>
<output>10</output>
10.

<result>10</result>