Tetration

Formula for density: d = m/V

Where m is mass, and V is volume.

Multiply both sides by V:

dV = m

m = dV

1. Calculate the total price of the three items:

3 * 29.95 = 3(30 - 0.05) = 90 - 0.15 = 89.85

2. Subtract the product ("solution of a multiplication) from the amount payed ($ 100):

100 - 89.85 = 10.15 

3. Stop buying CDs. Use Spotify or sth instead :P

4 - 2[6*3]/9 + 1

Order of operations:

PEMDAS: Please exuse my dear aunt Sally:

Paranthesis, exponents, multiplication (*) & division (:), addition (+) & subtraction (-).

4 - 2(6*3)/9 + 1 =

4 - 2(18)/9 + 1 =

4 - 36/9 + 1 = 

4 - 4 + 1 =

1

After zero years (at the beginning) you have $85:

a(0) = 85 

For each year that passes, the amount of money is multiplied by 1.085, and then $15 is added. 

a(n) = 1.085 * a(n - 1) + 15

We get:

a(1) = 1.085 * a(0) +15 = 1.085 * 85 +15 = 107.225 ≈ 107.26

a(2) = 1.085 * 107.26 + 15 ≈  131.34

And so forth until a(8) = ...

Pi is the ratio between a circle's circumference and it's diameter:

Pi = C/d

Since the diameter is twice as long as the radius ( d = 2r ) we have that:

Pi = C / 2r

Pi is an irratinal number, i. e. , it cannot be written as the ratio of two integers (positive - or negative whole numbers, or zero). This implies that pi has infinitely many decimals, and that pi cannot be represented as a repeating decimal. But pi is approximately 3.14

Use this formula:

V = pi * r² * h 

Where pi ≈ 3.14, r is the radius and h is the height. 

4⁵ = 4 * 4 * 4 * 4 * 4 = <Your answer>

No, it's rational!

The definition of a rational number is a number that can be written as a ratio of two integers (positive or negative whole numbers, or zero).

Your question doesn't by any chance have anything to do with acetic acid?

1.8 * 10^-5 + 3.25 * 10^-4 + 4.6 * 10² =

460 + 0.000 325 + 0.000 018 = 460.000 343 = 4.600 003 43 * 10²

1.8 * 10^-5 has two significant figures, so do 4.6 * 10².

Thus we can write: 460.000 343 ≈ 4.6 * 10²