In an experiment, zones of inhibition around four antibiotic discs are measured. The diameter of the zone for antibiotic W is 14 mm. Calculate the radius of the zone of inhibition for antibiotic W.

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Question

In an experiment, zones of inhibition around four antibiotic discs are measured. The diameter of the zone for antibiotic W is 14 mm. Calculate the radius of the zone of inhibition for antibiotic W.

Accepted Answer

7 mm — The radius is half of the diameter, so 14 mm ÷ 2 = 7 mm. Students commonly confuse radius and diameter, or multiply instead of dividing. In questions about zones of inhibition, diameter is usually measured directly across the clear zone.

Answer

3.14 mm

Answer

14 mm

Answer

28 mm

Answer

7 mm

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