The area of a triangle is 1/2(3x^3+x^2-15x-5) The height is 3x+1. Write an expression for the base b of the triangle.

All you must do is 15098000 divide by 63183000. With that decimal value you receive, the first two is the percentage, the third value, if higher than 4, then round up one percentage. 
Like such: 0.238 rounds to 0.24 which is 24% of the population was aged between 0 and 19.