Prove that for any natural n the number 3^(n+4)−3^n is divisible by 16.

Proved (See Explanation)

Step-by-step explanation:

Show that 3ⁿ⁺⁴ - 3ⁿ is divisible by 16.

This is done as follows

From laws of indices;

aᵐ⁺ⁿ = aᵐ * aⁿ.

So, 3ⁿ⁺⁴ can be written as 3ⁿ * 3⁴.

becomes

Factorize

3ⁿ * 5

5(3ⁿ)

The expression can not be further simplified.

However, we can conclude that when 3ⁿ⁺⁴ - 3ⁿ is divisible by 16, because 5(3ⁿ) is a natural whole number as long as n is a natural whole number.

  or  

step-by-step explanation:

if the four friends split the cost, p, of the pizza evenly, then each friend pays one-fourth of the cost of the pizza.

the expression is   or  

20

step-by-step explanation:

assuming you meant there are 24 pounds of apples in each case, if this is not what you meant, correct me so i can you further