CASE I. When the premium at a certain rate per cent. for infuring a fum, is required, the operation is the fame as in intereft or conimiffion. 1. What is the premium upon £537 15 9 at 64 për cent.? £ s. d. 537 15 9 To find the fum for which a policy should be taken out to cover a given fum. RULE. Take the premium from £100, and fay, as the remainder is to ico; fo is the fum adventured to the policy.* 1. It *Now, it is plain that, if I want to recover £92, I must, in this cafe, infure upon £100; therefore, to recover £759 I must infure upon £825, for when 8 per cent. for premium is deducted, I fhall have £759 remaining neat. For £825 fum infured upon at 8 per cent, 1. It is required to cover £759, premium 8 per cent ; for what fum maft the policy be taken ? 100 8 92: 100 :: 759 100 92)75900 (£825 Anf. 230 184 460 460 2. A merchant fent a veffel and cargo to fea, valued at £1525; what fum muft the policy be taken out for, to cover his property, premium 191⁄2 per cent. ? 100 19,5 80,5 100 :: 1525: £1894 8 24 Anf. CASE III. When a policy is taken out for a certain fum in order to cover a given fum: To find the premium, fay; As the policy is to the covered fum; fo is £100 to a fourth number, which, being taken from £150, will leave the premium. If a policy be taken out for £1250 to cover £500; what is the premium per cent.? 1250 500 :: ICO 100 A 1250)50000(40 and £100-40-£60 Anf. CASE CASE IV. When the policy for covering any fum and the premium per cent. are given to find the fum to be covered. RULE. Deduct the premium per cent. from 100, and fay, As 100 is to the remainder; fo is the policy to the fum required to be covered. If a policy be taken out for £1250 at 60 per cent.; what is the adventure, or fum to be covered? 100 100: 40 :: 1250 40 100)50000 (£500 Anf. CONPOUND INTEREST. Compound Intereft is that which arifes from the inter eft being added to the principal, and (continuing in the hands of the borrower) becomes a part of the principal, at the end of each stated time of payment. GENERAL RULE. Find the amount of the given principal, for the time of the firft payment, by fimple intereft; next find the intereft of that fum, or principal and add it as before, and thus proceed for any number of years, still accounting the last amount as the principal for the next payment The given principal being fubtract ed from the last amount, the remainder will be the com pound intereft. EXAMPLES. 1. What will £480 amount to in 3 years, at £6 per cent. per annum? Principal. When the rate is at 5 per cent. per annum. 1. Divide the principal by 20, and this quotient added to the principal, will be the amount for the first year, and the principal for the fecond 2. In like manner find the amount for every fucceeding year. When the rate is at 6 per cent. per annum, you may 1. Divide the principal by 20, and that quotient by 5: Thefe quotients, added to the principal, will be the amount for the first year, and the principal for the fecond. 2 In like manner obtain the amount for every lucceeding year. |