Is 30 a prime number , composite number, or neither?

30 is a composite number because it can be evenly divided by number other than 30 and 1. (i.e: 30/6=5, 30/5=6, 30/10=3).  

An example of prime number would be 5, since it can only be evenly divided by 5 and 1.

The constant of proportionality for the box is 6.

Step-by-step explanation:

  Given : The volume of a box (V) varies directly with its length (l). If the box has a volume of 90 cubic inches and a length of 15 inches.

We have to find the constant of proportionality for the box.

Since, The volume of a box (V) varies directly with its length (l)

Mathematically written as  V ∝ l

For removing proportionality, we multiply a proportionality constant k,

Thus, the equation V ∝ l

Becomes V = k l

Also given volume of 90 cubic inches and a length of 15 inches.

Substitute, V = 90 , and l = 15

We have,

90 = k (15)

Divide both side by 15, we get,

k = 6

Thus,  the constant of proportionality for the box is 6.