how to calculate % increase so same % when deducted gets the original number

  1. profile image49
    trkdposted 6 years ago

    how to calculate % increase so same % when deducted gets the original number

    if I have a model design that needs to be 100 mm finished length and I know shrinkage will be 15%, how do I calculate the model size before shrinkage?  the 100 mm is just chosen as example.

  2. oldhorse profile image66
    oldhorseposted 6 years ago

    You are trying to solve an equation:
    x = w * ( 1 - y )
    x = 100
    y = .15
    => 100 = w * .85
    w = 100 / .85
    w = ~117.647

 
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