Simplify 8 plus 4 squared minus 3(7) plus 3 squared
1 answer:
You might be interested in
Answer:
The cost of a 12 minute call to France is $ 3.63
Step-by-step explanation:
given:
The cost of 15 minute call to France = $ 4.29
The cost of 10 minute call to France = $ 3.19
To Find :
The cost of a 12 minute call to France = ?
Solution:
Let the flat fee be X
and the cost per minute be Y
so the 15 minute call to France will be
X + 15(Y) = 4.29---------------------------(1)
the 10 minute call to France will be
X + 10(X) = 3.19----------------------------(2)
Subtracting (2) from (1)
X + 15(Y) = 4.29
X + 10(Y) = 3.19
- - -
---------------------------------
5Y = 1.10
--------------------------------
Y = 0.22
So the cost per minute of a call = $0.22
substituting the values in (1)
X + 15(0.22) = 4.29
X + 3.3 = 4.29
X = 4.29 -3.3
X = 0.99
Now the cost of 12 minute call is
=>X + 12(Y)
=> 0.99 + 12(0.22)
=> 0.99 + 2.64
=> 3.63