Question

Beka and Melanie have 28 coins that are nickels and dimes. If the value of the coins is 1.95, how many nickels do they have ?

Answer 1

Beka and Melannie have 17 nickels.

Explanation:

Given:

Total number of nickels ans dimes =28

Total value of coins = $1.95

To find number of nickels.

Let number of nickels be =
`n`

So, number of dimes =
`Total\ coins\ -\ nickels=(28-n)`

1 nickel = $0.05

Value of
`n` nickels in dollars =
`0.05* n =0.05\ n`

1 dime = $0.10

Value of
`(28-n)` dimes in dollars =
`0.10(28-n)=2.8-0.1\ n`

Total value of nickels and dimes in dollars =
`0.05\ n+2.8-0.1\ n=2.8-0.05\ n`

So we have:

`2.8-0.05\ n=1.95`

Subtracting 2.8 from both sides.

`2.8-2.8-0.05\ n=1.95-2.8`

`-0.05\ n=-0.85`

dividing both sides by -0.05

`(-0.05\ n)/(-0.05)=(-0.85)/(-0.05)`

∴
`n=17`

∴ Beka and Melannie have 17 nickels.