Kendra has 22 dimes and 11 nickels
Solution:
Given, Kendra has $2.75 in dimes and nickels
Let dime = d, which is worth $0.1 each
[ we know that 1 dime = $ 0.1]
Let nickels = n, which is worth $0.05 each
[ we know that 1 nickel = $ 0.05]
She has twice as many dimes as nickels
Then, number of dimes = number of nickels x 2
m = 2n
We have to find how many are each coin does she have
Now, we know that, total amount worth = $2.75
Worth of dimes + worth of nickels = 2.75
Number of dimes x worth of 1 dime + number of nickels x worth of 1 nickel = 2.75
0.1m + 0.05n = 2.75
Plug in "m = 2n" in above equation, we get
0.1(2n) + 0.05n = 2.75
0.2n + 0.05n = 2.75
0.25n = 2.75
25n = 275
n = 11
Then, m = 2(n) = 2(11) = 22
Hence, Kendra has 22 dimes and 11 nickels.