1. 70 dimes and 33 quarters
2. 18 dimes and 9 nickels
3. 236 adults and 342 children
4. 12 quarters, 9 dimes
5. 9 nickels, 18 dimes
The total charges for the first club as a function of the number of rentals (x) are
... f1 = 25 + 2.50x
The total charges for the second club are
... f2 = 3.25x
We want to find x so that f1 < f2.
... f1 < f2
... 25 + 2.50x < 3.25x
.. 25 < 0.75x . . . . . . . . . . subtract 2.50x
... 25/0.75 < x . . . . . . . . . divide by the coefficient of x
... 33 1/3 < x
You must rent 34 videos or more to make the first club more economical.
V=(hπr^2)/3, π≈3.14, h=7, r=2
V≈29.3 cm^2
V = whl
V = 3 1/2 * 4 1/2 * 2
answer
3 1/2 * 4 1/2 * 2
15 3/4 * 2