College Algebra (11th Edition)

Part A: $\$2,549.25$Part B:$33,425.25 in 18 months
Part A: This is the formula for simple interest, where I is the interest, P is the principal, r is the rate, and t is the time in years. $I=prt$ Read the question and pull out the pertinent information. $P=\$30,900,r=5.5\%=0.055,t=1.5$years She will need to pay$\$2,549.25$ in interest. $I=(30900)(0.055)(1.5)=2549.25$ Part B: She must pay back the original amount with interest. $I+P=total=30900+2549.25=33449.25$ She must pay the bank \$33,449.25 in 18 months.