Answer: 
<u>Step-by-step explanation:</u>

Find the common denominator of 3 and 12 which would be 12.
Then we add the 2 fractions together to get 9/12.
Now we know that 9/12 of the guests chose chicken and beef.
We also know that 69 guests is equivalent to 3/12 which can be simplified down to get 1/4.
So now we can do 69x4 to get 4/4 which is also 12/12, the amount of guests .
69x4 is 276
Your final should be 276.
Answer:
$1.35
Step-by-step explanation:
x: quarter=$0.25
y: dime=$0.10
z: nickel=$0.05
so total amount of changes
= (0.25*x)+(0.10*y)+(0.05*z)
x=3, y=5, z=2
substituting into the eqn
total = (0.25*3)+(0.10*5)+(0.05*2)
= 0.75 + 0.5 + 0.1
= $1.35