Number System
A shopkeeper purchased 200 bulbs for Rs. 10 each. However, 5 bulbs were fused and had to be thrown away. The remaining were sold at Rs. 12 each. What will be percentage profit?
Let the digits be x and yTherefore, x + y = 12 .............(1)(10y + x) - (10x + y) Therefore, y - x = 4............. (2)Solving (1) and (2), y = 8 Therefore, x = 4There are two possible numbers 48 and 84. So the lowest no. is 48.
Let the greater and the smaller number be g and s respectively.gs = 2560g + s exceeds g - s by 64 i.e., g + s - (g - s) = 64i.e., 2s = 64 => s = 32.g = 2560/s = 80.