Together two computers cost $2700 per year to rent. If one costs twice as much as the other, what is the monthly cost of the most expensive one?

Answer 1

 a+b=2,700/year

a=2b

substitute 2b for a

2b+b=2,700/year

3b=2,700/year

 /3 /3

b=900/year

Put this back into our equation:

a=2b

a=2(900/year)

a=1,800/year

convert to monthly cost

a=1,800/year * 12 months/1 year

a=150/month