A small bore is designated 25H7. The lower (minimum) and

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A small bore is designated 25H7. The lower (minimum) and upper (maximum) limits of the . bore are 25.000 mm and 25.021 respectively. When the bore is designated as 25H8, then the upper limit is 25.033 mm. When the bore is designated as 25H6, then the upper limit of the bore in mm is

1. 25.001
2. 25.005
3. 25.009
4. 25.013

Correct Option: D

i = 0.45³√D + 0.0011)
= 0.45 ³√23.24 + 0.001 (23.24)
i = 1.31mm
IT7 = 16i = 16 × 1.31 = 21 µm
IT6 = 10i = 10 × 1.31 = 13.1µm
upper limit for Hole 25H₆ = 250.013mm