alleryStart learning →Per §10.4, the maximum coefficient of variation V (= σ/μ × 100) accepted by Indian Standard for concrete is:
AAbout 5 percent
BAbout 15 percent
CAbout 10 percent
DAbout 25 percent
Answer & Solution
Correct answer: B. About 15 percent
1. §10.4 reads: 'As per Indian Standard the coefficient of variation should not be more than 15%.'
2. With constant V the standard deviation σ rises with strength, so higher-grade concrete tolerates a numerically larger σ at the same V.
_Source: IGNOU ET-522 Block-3 Unit-10 Concrete Mix Design, §10.4, p. 8_
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