human
On Friday, Hank opened his used-bicycle store with a stock of bicycles, all fixed-up and ready to ride. Over the course of the day, he sold 10 bicycles and bought an additional 15 to fix up. On Saturday, he sold 12 bicycles and bought 8 more. And on Sunday, he sold 9 bicycles and bought 11 more. What was the net increase in the number of bicycles in stock in Hank's store over the three days?
assistant
How many bicycles did Hank sell? ** He sold 10+12+9=<<10+12+9=31>>31 bicycles.
How many bicycles did Hank buy? ** He bought 15+8+11=<<15+8+11=34>>34 bicycles.
What was the net increase in the number of bicycles? ** He now has 34-31=<<34-31=3>>3 more than at Friday's opening.
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