The percentage increase in the number of pens sold by a trader from Tuesday to Wednesday is same as the percentage decrease in the number of pens sold from Monday to Tuesday. On Wednesday the trader sold 16 pens more than those he sold on Tuesday. If the percentage decrease in sales from Monday to Tuesday is 20%, how many pens did he sell on Tuesday ?
A. 20
B. 96
C. 100
D. 80
Answer : D. 80
Explanation:
Let number of pens sold on tuesday be x given that the percentage increase in the number of pens sold by a trader from Tuesday to Wednesday is same as the percentage decrease in the number of pens sold from Monday to Tuesday.
Percentage increase in sales of pen from tuesday to wednesday = Percentage decrease in sales from monday to tuesday = 20% then on wednesday trader sold 16 more pens than those sold on tuesday.
So number of pens sold on wednesday = x + 16 and this is 20% more than number of pens sold on tuesday
[1 + (20/100) ] * x = x + 16
6x/5 = x + 16
x = 80
So number of pens sold on tuesday x = 80.