A speed curve’s height needs its bin width

A normalized molecular-speed probability density is nearly constant at 0.002 s/m across a narrow 25 m/s interval. A sample contains 80,000 molecules.

Approximately how many molecules lie in that interval?

Organize the givens & assumptions

Density in bin ≈ 0.002 s/m
Bin width = 25 m/s
Sample count = 80,000

Representative equilibrium ensemble; the nearly constant density approximation is valid only over the stated narrow bin. F(v) is a normalized probability density, not a count density.

A $160$
B $20000$
C $80000$
D $4000$

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