To find 1/3 of 180, we need to multiply 180 by 1/3, or divide 180 by 3. For this one, we will try both methods.
180/1 x 1/3 = 180/3 or 60
180 / 3 =60
Since we now know how much was sold, we need to find what is left. We need to subtract 180 by 60.
180-60=120
So 120 bottles are left. Now, since 3/5 of 120 were sold the next day, we need to multiply 120 by 3/5.
120/1 x 3/5 = 360/5 or 72.
Now we know that 72 bottles were sold on Saturday. Subtract 120 by 72 to know how much is left in total.
120-72=48
60 bottles of water were sold on Friday.
72 bottles of water were sold on Saturday.
There were 12 more bottles sold on Saturday than Friday.
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hope it helps