Mr. Gleicher – AP Biology Name: __________________ How to Solve Hardy-Weinberg Problems THE BASICS p2 + 2pq + q2 Frequency of Homozygous Dominant Individuals Frequency of Heterozygous Individuals Frequency of Homozygous Recessive Individuals p+q=1 Frequency of Dominant Allele Frequency of Recessive Allele SOLVING PROBLEMS Most problems require similar steps. Here’s a list of things (usually) that need to be done in order to solve most problems: 1. Find number of recessive phenotype individuals OR homozygous recessive individuals in a population. 2. Convert to a frequency (percent as a decimal). This is q2. 3. Take the square root. This is q. 4. Subtract q from 1. This is p. 5. Square p. This is p2 and represents the frequency of homozygous dominant individuals. 6. Find 2pq. This represents the frequency of heterozygous individuals. 7. Multiply each value (p2, 2pq, q2) by the overall population size to find numbers of individuals with these traits, if necessary.