Number System
The population of a town increases by 15% in the first year and decreases by 25% in the second year. If its current population is 168480 then what will be its population after two years ?
Let the consecutive odd number be x, x + 2, x + 4 and x + 6 respectively.According to the question x + x + 2 + x + 4 + x + 6 = 104 = 4x + 12 = 104 = 4x = 104 - 12 = 92∴ x = 92/4 = 23∴ Required number = x + 4= 23 + 4 = 27
Let the first number be x and the second number be y.∴ y² = 82 - 15 = 64 - 15 = 49∴ y = 7∴ x² + 73 = 568= x² + 343 = 568= x² + 568 - 343 = 225∴ x = √225 = 15∴ 15 x 3/5 = 9