BACK 1.If Rs.10 be allowed as truedscount on a bill of Rs.110 at the end of a certaimn time ,then discount allowed on the same sum due at the end of double the time.. sol: Amount=Rs110 TrueDiscount=Rs10 Present worth=Amount-TrueDiscount =Rs110-10 =Rs.100 SI on Rs.100 for a certain time =Rs.10 SI on Rs.100 for doube the time =Rs.20 TrueDiscount on (100+20)=120-100 =Rs20 TrueDiscount on Rs.110 =(110*20)/120 =Rs18.33 2.A man wants to se hs scooter .There are two offers one at Rs12000 cash and other at acredit of Rs12880 to be paid after 8 months ,money being at 18% per annum which is better offer? Sol: offer1=Rs12000 offer2 Present worth= (Amount*100) /(100+(R*T)) =Rs.12880*100/(100+(18*(8/12)) =Rs11,500 The first offer is better as if he gains 500/- if he sells at Rs.12000 is better 3.Goods were bought for Rs.600 and sold the same day for Rs.688.80 at a credit of 9 months and thus gaining 2% rate of interest per annum is sol: MethodI: Amount=Rs.688.50 Time=9.12 Gaining 2%----------->Presentworth=102%of 600=(102*600)/100 =Rs.612 Presentworth=(Amount*100)/(100+(T*R)) 612=(688.80*100)/(100+((9/2)*R)) =>R=162/3% MethodII: TrueDiscount=688.50-612 =Rs.76.50 Rate=TrueDiscount*100/(P.W*T) =(76.50*100)/(612*(9/12)) =162/3% 4.The present worth of Rs.1404 due in 2 equal halfyearly instalments at 8% per annu8m S.I is SOl: Presentworth=(Amount*100)/(100+(T*R)) PresentWorth=Presentworth of Rs.702 6 months hence + Presentworth of Rs.702 1yr hence = (702*100)/(100+(1/2*8)) + (702t*100)/(100+(1*8)) =Rs.1325 BACK |