192k views
3 votes
dennis mowed his next door neighbors lawn for a handful of dimes and nickels, 80 coins in all. upon completing the job he counted out the coins and it came to 6.60. how many of each coin did he earn?

User Gbachik
by
4.8k points

1 Answer

3 votes

Answer:

52 dimes and 28 nickels

Explanation:

n = number of nickels

d = number of dimes

n+d = 80 the number of coins he got

Multiply the number of nickels times .05 plus the number of dimes times .10 to equal the amount of money he got

.05n + .10d = 6.60

Divide this equation by .05

.05n/.05 + .10/.05 = 6.60/.05

n + 2d = 132

n+d = 80

Multiply by -1

-n-d=-80

Add this to n+2d = 132

n+2d=132

-n-d=-80

-------------------

d = 52

Now we need to solve for n

n+d = 80

n+52 = 80

Subtract 52 from each side

n+52-52= 80-52

n = 28


User Jimba Tamang
by
4.3k points