John had a stock of 620 books in his bookshop. He sold 50 on Monday, 82 on Tuesday, 60 on Wednesday, 48 on Thursday and 40 on Friday. What percentage of the books were not sold?
Options: A) 54.84% B) 36.5% C) 46.5% D) 56.5% E) 66.5%
Let N be the total number of books sold. Hence   N = 50 + 82 + 64 + 78 + 135 = 280   Let M be the books NOT sold   M = 620 - N = 620 - 280= 
<gadget id="calculator">620 - 280</gadget>
<output>340</output>
340   Percentage   Books not sold / total number of books= 340/620= 0.55 = 54.84%   correct answer 54.84%
<result>A</result>
John had a stock of 620 books in his bookshop. He sold 50 on Monday, 82 on Tuesday, 60 on Wednesday, 48 on Thursday and 40 on Friday. What percentage of the books were not sold?