A stack of nickels and dimes is worth $2.55. find the number of nickels if the number of dimes is 12 less than twice the number of nickels

Question

anonymous · Answer

i am sorry 
please mention the value of 1 nickel and 1 dime so i can solve it
i live in a country where i dont use this currency

anonymous · Answer

okay go it!
nickel- 5cents
dime 10 cents

anonymous · Answer

easy!

anonymous · Answer

$$No of dimes+12=2*No. of nickels \right ????$$

anonymous · Answer

you know that the value of all the coins is 2.55 dolls.
there fore 
0.10*(no of dimes)+0.05(no of nickels)=2.55 .............(1)
no of dimes= 2* no of nickels -12 according to the question .......(2)
let us put this in eq-(1)
we get
0.10(2x-12)+0.05x=2.55
where x is the number of nickels
solve for x we get
x=15
let us put thiis value in (2)

we totally get 
1)no of dimes =18
2)no of nickels =15

there ya go!