Question

Julio has $2.75 in his pocket in nickels and dimes . The number of dimes is 10 less than twice the number of nickels. Find the number of each type of coin

Answer 1

A Dime is worth 2 nickels which equals 10.

let no of dimes be x

let no of nickles be y

so as per the data mentioned in the question , x=2*y-10

total amount = $2.75 

so total amount should comprise of nickels and dimes

x*dimes + y*nickels = $2.75

x*( 2 nickels)+ y *nickels = $2.75

=> nickles( 2x+y) = $ 2.75

but 20 nickels = 1 dollar

nickles(2x+y) = 2.75*20 nickels

cancelling nickles on both sides

2x+y = 55

already we know that x= 2y-10 

so 2(2y-10) +y= 55

4y-20+y=55

5y -20 =55

So, your answer is 55.

Answer 2

Answer:  15 nickels and 20 dimes

Step-by-step explanation:

Nickels (N) = N and each is worth $0.05

Dimes (D) = 2N - 10 and each is worth $0.10

0.05N + 0.10D = 2.75

0.05N + 0.10(2N - 10) = 2.75

0.05N + 0.20N - 1.00 = 2.75

             0.25N - 1.00 = 2.75

             0.25N           = 3.75

                    N          =   15

D = 2N - 10

   = 2(15) - 10

   =  30  - 10

   =     20

Check:

0.05(55) + 0.10(20) = 2.75

   0.75    +     2.00   = 2.75

            2.75           = 2.75 $\checkmark$