4. D
12/15 isn't the same as 30/40. 12/15=0.8, while 30/40=0.75. All the other options are equal.
5. C
Of course, you could figure this out by plugging in all the answers, and seeing which ones make the two sides equal, however, cross multiplying (multiplying the top of one fraction with the bottom of the other fraction) would be much faster. This will be your equation: 8*46=18*n. After combining like terms and dividing, you should find that n=20.
6. A
This problem is basically the same as #5. Cross multiplying so the equation you get will be 0.6*1.2=1.6*w. W should be 0.45.
Hope this helps!!
Answer:

Step-by-step explanation:
Area of compound shapes = Area of shape A + Area of shape B
Area of this shape = (L x B) + (L x B)
= (5 x 3) + (6 x 2)
= 15 + 12
= 
The formula for this sequence is an=2.6+(n-1)*1
recursive formula= an=a(n-1)+1.2
therefore the answer being 6.2

Answer you are looking for is 13
10. The numbers on the horizontal line would be:
1, 2, 3, 4, 5, 6
11. Count how many of each number there is.
1- 3
2- 4
3- 2
4- 3
5- 2
6- 2
So numbers 1 and 4 will both have 3 dots above them and numbers 3, 5, 6 will have 2 dots above them.