what i can think of is:
create an excel.
first column will be value,
2nd column will be gst 12% or just 1.12 for multiplication purpose
3rd column will have multiplication of 1st and 2nd column
copy the value of 3rd column to where you want
maybe this can help you a little better.
ashokkarale
MD_Farhan1
Ajay_Mishra
postwick
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chandreshsinh.jadeja
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vrdabberu
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