Suppose that the world's current oil reserves is R

=

1900

billion barrels. If, on average, the total reserves is decreasing by

24

billion barrels of oil each year, answer the following:
A.) Give a linear equation for the total remaining oil reserves,
R
, in billions of barrels, in terms of
t
,
the number of years since now. (Be sure to use the correct variable and Preview before you submit.)
R
=

B.)
9
years from now, the total oil reserves will be
billions of barrels.

C.) If no other oil is deposited into the reserves, the world's oil reserves will be completely depleted (all used up) approximately
years from now.
(Round your answer to two decimal places.)

  A)  R = 1900 -24t

  B)  1684 billion barrels

  C) 79.17 years

Step-by-step explanation:

Reserves start at 1900 billion barrels and decrease by 24 billion barrels each year. The value for t=0 is 1900; the value for t=1 is 24 less.

  R = 1900 -24t

__

For t=9, the reserves will be ...

  R = 1900 -24(9) = 1900 -216 = 1684 . . . . billion barrels

__

The reserve will be 0 when ...

  0 = 1900 -24t

  24t = 1900 . . . . . add 24t

  t ≈ 79.17 . . . . divide by 24

Reserves will be gone in about 79.17 years.

the final amount you will pay is $68.04.

the tip is determined by the pre-tax amount, so we calculate the tip based on the original bill, not after we've added sales tax.

to find the tip:

we can divide 54.00 by 100 to get 1% of 54. then we multiply that by 18.

54 / 100 = .54

.54 x 18 = 9.72

tip = 9.72$

to find the tax:

we can divide 54.00 by 100 to get 1% of 54. then we can multiply that by 8 to get 8%.

54 / 100 = .54

.54 x 8 = 4.32

tax= 4.32

now we can add the tip and tax to the bill to get our total.

54 + 9.72 + 4.32 = 68.04

total: $68.04

step-by-step explanation: