Multiplication and adding two different line items
Class 1 is starting from 7 mar and class 2 is from 21 mar
Now i need to write formula in Total
For example in 21 mar Column, 62 * 2 (which is week 3 * prod ) and 80 * 2 (which is Actual Start  Day 1 * Prod (Next Wave))
(62*2)+(80*2) = 284  the formula in Total is not correct now
I try averaging the Prod and Prod Next Wave but the values can be like 8,3 so averaging not giving accurate calculations
Answers

What is Total currently having as it's line item? This will show where the issue is, might be that brackets aren't coming through correctly.
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the Formula of Total is
('Actual Start  Day 1' + 'Week 2' + 'Week 3' + 'Week 4' + 'Week 5' + 'Week 6' + 'Week 7' + 'Week 8') *Prod* + ('Actual Start  Day 1' + 'Week 2' + 'Week 3' + 'Week 4' + 'Week 5' + 'Week 6' + 'Week 7' + 'Week 8') * Prod  Next Wave'
it added 80 and 62 before multiplication0 
So it looks like you'll need to be able to identify which of the values are Week 07 Mar and which are Week 21 Mar, otherwise the formula will continue to duplicate up.
It'll probably need an IF ... THEN ... ELSE ... to get the right number.
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