The cost of buying all slippers is 6.5x yuan, and the money for selling shoes is 12(x-5) yuan.
According to the meaning of the question, it is: 12(x-5)-6.5x= 105.
To solve this equation, x=30.
A: The store bought 30 pairs of slippers.
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Naughty and smiling went to buy fruit. Naughty bought a basket of apples at 1 and smiling bought a basket of pears at 1.
What percentage of the sum of this basket of apples and pears did they buy?
Solution: Suppose a basket of apples ***a and a basket of pears * * * B.
Naughty bought an a/6 apple and smiled and bought a b/3 pear.
Therefore, the ratio of two fruits to total fruits is: (a/6+b/3)/(a+b)=(a+2b)/[6(a+b)].
You must also know the multiple/score relationship between a basket of apples and a basket of pears before you can calculate the result.