Victoria and her younger brother came to know about a scheme from their friends. Both of them used to get some pocket money every month. When they heard about the scheme, they counted up the money they both had together. They had \$2,500. According to the scheme, if they invested the money they had at the rate of 12%, they would earn an interest of \$2,100 in 7 years at simple rate of interest, but the company changed the scheme. According to the new scheme, the new rate of interest was 10% less than double the earlier rate. Now what is the increase in the interest they would have earned?