Project ForgeEngineering Mathematics
Calculus
GATE 2017
Medium
The standard deviation of linear dimensions P and Q are 3 μm and 4 μm, respectively. When assembled, the standard deviation (in μm) of the resulting linear dimension (P+Q) is __________.
5 μm(± 0.1 accepted)
Explanation
For independent random variables, variances add: σ(P+Q) = √(σP² + σQ²) = √(3²+4²) = √25 = 5 μm.
Source: GATE ME 2017 Session 2 (ME-2) (2017)
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