Bill started west on road U. S. 50, riding a bicycle at an average rate of 9 mph. Four hours later Charles started after Bill on a motorcycle and overtook him in 2 hours. What was Charles rate? Which equation could be used to solve for Charles rate if it is represented by x

At the beginning of 1974/75,2 years a man invested #2000 in a bank at 12.5% compound interest, if it degree #650 at the end of each two years to pay his son's school fees, after payment of interest to pay his son's school fees, how much did he have left at the beginning of the 1978/79 school year?