Ineed an answer and can you explain how ya got it for numbo six

First, 45 is the total number of students. So you have to add the ratio: 2+3=5. Since you are finding the number of sixth graders, you need to use the ratio 2.

Sixth graders : All = x : 45

2 : 5 = x : 45

You could change this to fractions and solve it.

2/5 = x/45

x = 18

So there are 18 sixth graders.