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Reinforced Cement Concrete

Characteristic Compressive Strength of Concrete -I

Characteristi...

Question

Characteristic strength of M20 concrete is 20 MPa. What is the number of cubes having 28 days compressive strength greater than 20 MPa out of 100 cubes made with this concrete?

A

All

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B

95

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C

80

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D

50

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Solution

The correct option is B 95
The characteristic strength is that below which not more than 5% of the test results are expected to fall. Thus 95% of cubes will have strength more than characteristic strength.

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