aiO ,, ARITHMETIC. 



EXAMPLES. 



1. What is the present worth of an annuity of looi. td 

 continue 5 year^, at 6 per cent, pet annurfi> simple interest ? 



ic6 I 100 :: 100 : 94-3396= present worth for i year. 



112 : 100 : : 100 ; 89*2857= 2d year. 



118 : 100 :: 100 : 84*7457=: 3d year. 



124 : 100 : : 100 : 80*6451= 4th year. 



130 : ICO : : 100 : 76*9230= 5th year. 



425 "939 1 = 425I. 1 8s. 9-Jd. = present 

 worth of the annuity required. 



2. What is the present worth of an annuity or pension 

 of 5001. to continue 4 years, at 5 per cent, per annum, 

 simple interest ? 



Ans. 1782!. 58. 7d. 



To find the Ammmt of an Avjin'ity at Compound Interest, 

 RULE.* 



I. Make i the first term of a geometrical progression^ 

 and the amount of il. for one year, at the given rate per 

 cent, the ratio. 



2. Carry 



The other two theorems for the time and rate cannot be given 

 in general terms. 



* Demonstration. It is pdain, that upon the first year's an- 

 nuity, there will be due as many years' compound interest, as the 

 given number of years less one, and gradually one year's interest 



less 



