Question

Present Value	Years	Interest Rat	Future Value	Equation
$560		7%	$1,389
$810		8%	$1,821
$18,400		9%	$289,715
$21,500		11%	$430,258

Solve for the unknown number of years (round to 2 decimal places)

Answer 1

Please refer to below spreadsheet for calculation and answer. Cell reference also provided.

в с D E Present Value Years Interest Rate Future Value Equation Years Calculated with Manual equation Manual Equation 7% $560 $810 $18.400 $21,500 13.43 10.53 31.99 28.71 $1,389 =NPER(D4,,B4,-E4,0) $1,821 =NPER(D5,,B5,-E5,0) $289,715 =NPER(D6,,B6,-E6,0) $430,258 |=NPER(D7,,B7,-E7,0) 13.43 =LOG(E4/B4)/LOG(1+D4) 10.53 =LOG(E5/B5)/LOG(1+05) 31.99 =LOG(E6/B6)/LOG(1+D6) 28.71 =LOG(E7/B7)/LOG(1+D7) 8% % 11% =LOG(FV/PV)/LOG(1+i) 9

Cell reference -

ДА В D E Present Value Years Interest Rate Future Value Equation Years Calculated with Manual equation Manual Equation 560 810 =NPER(D4,,B4,-E4,0) 0.07 =NPER(D5,,B5,-E5,0) 0.08 =NPER(D6,,B6,-E6,0) 0.09 =NPER(D7,,B7,-E7,0) 0.11 1389 1821 289715 430258 =FORMULATEXT(C4) (=LOG(E4/B4)/LOG(1+D4) =FORMULATEXT(G4) =FORMULATEXT(C5) (=LOG(E5/B5)/LOG(1+D5) =FORMULATEXT(G5) =FORMULATEXT(C6) =LOG(E6/16)/LOG(1+D6) |=FORMULATEXT(66) =FORMULATEXT(C7) |=LOG(E7/B7)/LOG(1+D7) |=FORMULATEXT(G7) =LOG(FV/PV)/LOG(1+i) 18400 21500

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