A man sold a horse at 10% profit. Had he bought it at 20% less and sold for tk. 10 more, he would have made profit of 40%. What is the cost price of the horse?

Let the CP be Tk. 100. So, SP is Tk. 110. The new CP is Tk. 80. So the new SP =140%(80)= Tk. 112 So the difference of SP’s = Tk. 2. Now, if the difference is 2, CP is 100 So, when the difference is 10, the CP is (100 * 10 / 2) taka

                                                            = 500 taka