(adsbygoogle = window.adsbygoogle || []).push({}); [Solved]Stats question regarding mean

1. The problem statement, all variables and given/known data

Yo.Exam marks,X've mean 70 and standard deviation 8.7.The marks need to be scaled using the formula Y=aX+b so that the scaled marks,Y've mean 55 and standard deviation 6.96.Find the values of a and b.*From the answer sheet -to form equation for mean it's 55=70a+b,why is there "b" in there?

2. Relevant equations

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3. The attempt at a solution

55=70a+b

U don't need this,I just need some clarity on the above * thing.Pls?

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# Homework Help: Stats question regarding mean

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