multiple results changing a single cell

Story so far. In a work book have several dozen calculations based on a single cell lets call it C5

In a second workbook I have 5 columns of data with multiple rows derived from the value in C5

Column 1 in the second book has the value C5, How can I utilize the one workbook to use diffent values for subsequent columns in the second workbook

Workbook #1

C5 = 300

b10 = c5 *100
b11 = c5 /3.1415926
b12 = etc

Workbook #2

A1 A2 A3 A4
300 (C5) 200 500 700

B10 = 300*100 C10 = 200 *100 D10 = 500*100
B11 = 300/3.1415926

I know this is confusing, please help

need help

Want a tracker in which say there are 3 work stations (Starting from A, B and C)which has cycle time of its own. Say 1 product has delivery date of 30 March.

Work station C has cycle time of 3 days
Work station B has cycle time of 4 days
Work Station A has cycle time of 2 days

So to get delivery by 30 March, excel should calculate based on lead time when the activity needs to be started. If the date after substracting cycle time comes Sunday or holiday it should further substract 1 or 2 days as applicable and give the next date.

Can you help me with equation to be sued which will give desired results.