John had a stock of 1400 books in his bookshop. He sold 75 on Monday, 50 on Tuesday, 64 on Wednesday, 78 on Thursday and 135 on Friday. What percentage of the books were not sold? Options:  A) 50.4%  B) 71.3%  C) 66.5%  D) 34.9%  E) 43.5%
Let N be the total number of books sold. Hence   N = 75 + 50 + 64 + 78 + 135= 
<gadget id="calculator">75 + 50 + 64 + 78 + 135</gadget>
<output>402</output>
402   Let M be the books NOT sold   M= 1400 - N = 1400 - 402= 
<gadget id="calculator">1400 - 402</gadget>
<output>998</output>
998   Percentage   71.3%ooks not sold / total number of books= 998/1400 = 0.713 = 71.3%   correct answer 71.3%
<result>B</result>
John had a stock of 1400 books in his bookshop. He sold 75 on Monday, 50 on Tuesday, 64 on Wednesday, 78 on Thursday and 135 on Friday. What percentage of the books were not sold?