Question 1
Paper 1Medium7 marksThe Northgate Credit Union offers simple interest at 2.7% per year on the original deposit. Leila deposits $2400 and makes no further deposits or withdrawals. Let be the balance, in dollars, at the end of years.
(a)[1]
Calculate the common difference between consecutive year-end balances.
(b)[2]
Show that
(c)[1]
Hence, determine the first whole year at the end of which the balance exceeds $3000.
(d)[3]
A report summarizes the mean of the balances at the ends of years 1 to 10. Write the sum of these balances in sigma notation and hence determine the mean.