Bimodal distribution in statistical world mean a continuous distribution with two different modes. Generally it is considered that the height of men are more than those of women so if we look at both of them and compare we are talking in bimodal distribution; while if we look separately than men and women are unimodal.
Binomial distribution should not be confused with bimodal distribution. The frequency in which the distribution of any probability of any specific number of successes in an arbitrary no. Of repeated independent trials.
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