Kendra has $2.75 in dimes and nickels if she has twice as many dimes as nickels how many are each coin does she have

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.

the expected value of the random variable : 0, 1 and 2

step-by-step explanation: