Pens that used to cost Tk. 150 for a package of 3 now cost Tk. 300 for a package of 5. What is the percent increase in the pr...

Answer: 
20%
Pens that used to cost Tk. 150 for a package of 3 now cost Tk. 300 for a package of 5. What is the percent increase in the price of these pens?