Pair of Liner Equation in Two Variable

Susan invested certain amount of money in two schemes A and B, which offer interest at the rate of 8% per annum and 9% per annum, respectively. She received Rs  1860  as  annual  interest.  However,  had  she  interchanged  the  amount  of investments in the two schemes, she would have received Rs 20 more as annual interest. How much money did she invest in each scheme?