If 3/2 ÷ 1/4 = n, then n is between:
a. 1 and 3
b. 3 and 5
c. 5 and 7
d. 7 and 9

3/2 ÷ 1/4  is 3/2 x 4/1 (the reciprocal)
Since 3/2 is the same as 1  1/2 we are asking how much are 4 x 1 1/2
Think money
1 1/2 is like $1.50
If I had $1.50 two times - I'd have $3.00
If I had $1.50 four times - I'd have twice as much or $6.00

Now I know that 6 is between 5 and 7 so answer c. is correct
You could also just multiply 3/2 x 4/1 but I think my explanation helps you understand it better than just using the multiplication algorithm.

Yes. there is a constant ratio of number of calories to gram of protein.12/3=24/4=32/8=44/11=4