Inter-related cells

Hi, I'm just now trying to use excel for the first time to create a database and I haven't been able to find the information on how to get the cells to do what I need. Here's what I'm trying to do:

I enter a food item in A1 (e.g. Oats).
B1=F1*3.6 (calculates the total calories)
C1=F1*3.6*0.67 (calculates carb calories)
D1=F1*3.6*0.12 (calculates protein calories)
E1=F1*3.6*0.21 (calculates fat calories)
I enter the gram amount in F1

This works fine. But what I would like to also do is to be able to enter a calorie amount in B,C,D, or E and for the other cells to calculate the rest, including the gram amount. Would really appreciate any help on this.

Thanks in advance