Basics of Finan...

What will be the compound interest on a sum of Rs.25000 after 3 years at the rate of 12 per cent p.a.?

A finance company declares that, with compound interest rate, a sum of money deposited by anyone will become $$8$$ times in three years. if the same amount is deposited at the same compound-rate of interest, then in how many years it will become $$16$$ times?

The population of a town was 1,60,000 three years ago. If it increased by 3%, 2.5% and 5%, respectively, in the last three years, then what is the present population?

The half life of Uranium - $$233$$ is $$160000$$ years i.e., Uranium $$233$$ decays at a constant rate in such a way that it reduces to $$50\%$$ in $$160000$$ years. in how many years will it reduce to $$25 \%$$?

In what time will $$Rs.\ 1000$$ amount to $$Rs.\ 1331$$ at $$10\%$$ per annum if interest is compounded anually?

A sum is invested for $$3$$ years compounded at $$5\% ,10\% $$ and $$20\%$$ respectively. In three years, if the sum amounts to Rs. $$16,632$$, then find the sum.  

The population of a town increases annually by $$25 \% $$ if the preset population is $$1$$ crore, then what was the difference between the population three years ago and two years ago?

The annual increase in the population of a town is 10%. If the present population of the town is 180,000, then what will be its population after two years ?

A machine depreciates in value each year at the rate of $$10\%$$ of its previous value. However every second year there is some maintenance work, so that in that particular year depreciation is only $$5\%$$ of its previous value. If at the end of the fourth year the value of the machine stands at Rs. $$146205$$, then find the value of the machine at the start at the first year?

A sum of money at compound interest (compounded annually) doubles itself in $$4$$ years. In how many years will it amount to eight times of itself ?