Sam has a payment of $250 due in 6 months and another payment of $1000 is due in 10 months. Calculate the value of a single payment to be made in 8 months that is equivalent to these two payments if money earns 5.5% p.a. simple interest. Use 'today' as the focal date. Mary has to repay $3000 due in 2 months and another payment of $5600 due in 8 months. Calculate the value of a single payment to be made in 4 months that is equivalent to these two payments if money earns 4% p.a. simple interest. Use 4 months as the focal date