Question

Last summer, Betty earned $4200 by painting houses. She invested
some of the money in a savings account that paid 3.5%/year and the
rest in a government bond that paid 4.5%/year. After one year, she has
earned $174 in interest. How much did she invest at each rate?

Answer 1

x*(1.035) + (4,200-x)*(1.045) = 4,374.00

1.035x + 4,389.00 -1.045x = 4,374.00

15.00  = .01x

x = 1,500  so x (1,500) invested at 3.5% and  

(4,200 - 1,500) (or 2,700) invested at 4.5%