John pays for half the cost of raising a child.  It cost $10,000 a year for the first 8 years and then twice that much per year until the child is 18.  University tuition then costs $250,000.  How much did it cost?
The first 8 years cost 8*10,000=$<T>multiply(8, 10000)=80000
The next 18-8=<T>subtract(18, 8)=10 years
They cost 10000*2=$<T>multiply(10000, 2)=20000 per year
So they cost 20,000*10=$<T>multiply(20000, 10)=200000
So the cost was 200,000+80,000=$<T>add(200000, 80000)=280000
Adding in the cost of tuition brings the cost to 250,000+280,000=$<T>add(250000, 280000)=530000
Since John pays for half the cost of raising the child, he pays $530000/2 = <T>divide(530000, 2)=265000.0
