8192 grams of radioactive material decays every hour in a geometric fashion. After 3 hours of decay, 128 grams of radioactive material remains. Assuming the decay continues at the same rate, determine the exact amount of radioactive material that would remain by the 7th hour of decay.

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?