ans.21%
The cost of 11 items are = Tk. 10
The cost of 1 items are = Tk.$\frac{11}{10}$
The selling price of 10 items are = Tk.11
The selling price of] items are = Tk.$\frac{10}{11}$
The profit from 1 item = ($\frac{11}{10}$-$\frac{10}{11}$)Tk.=$\frac{121-100}{110}$=Tk.$\frac{21}{110}$
TK.$\frac{10}{11}$makes profit=tk $\frac{21}{110}$
Tk. 100 makes profit=$\frac{21\times 11\times 100}{110\times 10}$=21%
ans: The two trains will meet after $\frac{22}{5}$or 4.4 hours and the distance from Dhaka is 88 miles.
Per hour two trains cover = (20 + 25) = 45 miles
Two train cover 45 miles in = 1 hour
Two train cover 1 miles in=$\frac{198}{45}$ hour
=$\frac{22}{5}$hour
The train starts from Dhaka takes = 1 hours in = 20 miles
The train starts from Dhaka takes = $\frac{22}{5}$hour in
=$\frac{22\times 20}{5}$=88 miles
