A word problem on percentages

Percentages are used to express how large one quantity is, relative to another quantity. The first quantity usually represents a part of, or a change in, the second quantity, which should be greater than zero. For example, an increase of $ 0.15 on a price of $ 2.50 is an increase by a fraction of 0.15 / 2.50 = 0.06. Expressed as a percentage, this is therefore a 6% increase.

Let's see a word problem on it.

Question:-

A waitress earn an average tip of 12% of the cost of the food she serves.If she serves $ 375 worth of food in one evening ,how much money in tips will she earn on average.

Answer:-

Waitress serves food worth=$375

She earns a tip=12%

     So.
           12% of $375


       12
      ----- * 375
       100

      12*375
     ---------
       375

       4500
   =  -------
        100

   =$45

 So the waitress earn a tip of $45.

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