Ineed with this simple question and i need full work shown

I believe the easiest way to do this is to set up a proportion.
We can also rephrase this to help.
We know that 30 is 5% of the total. From here we can set up a proportion.
30/x = 5/100
3000 = 5x Cross multiply
600 = x Divide both sides by 5

600 should be the answer. To test the answer, do 30/600 and you should get 5% or .05.

Hope this helps! Be sure to message me if you have any questions!

5% of n = 30 where n is total six graders surveyed

0.05n=30
n=30÷(0.05)
n=600

1.17+3.99a. you combine the terms with a to create 3.99 and the 1.17 stays because it has no like terms or a variable