Calculate the interest for a year interest/year = percentage × deposit interest/year = 7.5% × 300 interest/year = interest/year = interest/year = 22.5 She will get $22.5 in a year
Calculate interest in 5 years interest in 5 years = interest per year × 5 interest in 5 years = 22.5 × 5 interest in 5 years = 112.5 She will get $112.50 in 5 years