If pens cost 9 cents each, what equation could be written to calculate the cost, c, of any number of pens, p?

The total cost (in dollars) of p pens is C = 0.09 p

Step-by-step explanation:

The cost of each pen = 9 cents

Now, 1 cent  = $0.01 cents

⇒ 9 cents  = $0.09

So, the cost of  1 pen = $0.09

The number of pens purchased= p

Let the total cost of p pens = c

Also, the cost of p pens = p x ( Cost of 1 pen)  = p ( $0.09)  = 0.09 p

or, C = 0.09 p

Hence the total cost (in dollars) of p pens is C = 0.09 p.

unless you made a typo, the answers are both a and c.

step-by-step explanation:

1.5/3 is .5 whereas 3/9 is .3333333 not proportional

22/33 is .66666 and 4/6 is also .66666 proportional

2/4 is .5 whereas 142/213 is .66666 not proportional

14/7 is 2 and 7/3.5 is also 2 proportional

you could've also checked it by doing this simple division:

if the larger fraction divides with the smaller fraction to equal 1, it is proportional. so let me show you what i mean:

when i divide 22/33 by 4/6 i get 1, so we know it is proportional, and it is the same with 14/7 and 7/3.5. now if i divide 3/9 by 1.5/3 i get .66666 so therefore we know it is not proportional.

there are many ways to do this so i wanted to show you some possible ways.