Answer:
48.30
Step-by-step explanation:
First determine the tip
42 *15%
42 *.15 =6.30
Add this to the amount of the tip
42 + 6.30 =48.30
The total amount is 48.30
Answer:
10.7 + 2 + 10.9 10.9 x 30.9 is 336.81
Step-by-step explanation:
BIG BRAIN POWER
From trigonometry we know that:
if 
then,
(where
is an integer)
This can be rewritten in degrees as:
.............(Equation 1)
Now, in our case, 
Therefore, (Equation 1) can be written as:
..........(Equation 2)
Now, to find the correct options all that we have to do is replace n by relevant integers and find the values of
that match.
For n=2, (Equation 2) gives us:
.
Thus, 
Now, we know that: 
Let n=-1, then:

Thus, 
Likewise, 
Only the last option
will never match
because no integral value of
will ever give 
Thus the last option is the correct option.