Question

John had a stock of 1200 books in his bookshop. He sold 75 on Monday, 50 on tuesday,64 on wednesday 68 on thursday and 163 on friday. What percentege of the books were not sold??

Answer 1

First you add up all of the sold books
the subtract the sold books by the total
then you divide the unsold books by the amount of books he started with
then you change the decimal to a percent

75+50+64+68+163=420
1200-420=780
780/1200=.65
65%

Answer 2

First we have to find how many books he sold, so
75+50+64+68+163=420 - total books sold
Now im finding how many books are not sold
1200-420=780
Now we can use proportion, so
1200 ---------100%
780------------x

x=$x= \frac{780*100}{1200}=65%$ 65% of all books are not sold.