11. John invested $4000 at an interest rate of 13 4
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. How much interest did John earn in one year? 12. a) 77 cm exceeds 52 cm by what percent? b) $24.00 increased by 7%% is how much? c) $45.00 is what percent less than $210.00? d) 15 kg decreased by 14% is how much? 13. A rough casting with a mass of 24 kg, after having been finished on a lathe, has a mass of 221/2 kg. What is the percent of decrease in mass?