Credit Sprint / Practice problems / Hardy-Weinberg allele frequency

Hardy-Weinberg allele frequency practice problems

Biology Unit 7. Try each one, then open the worked solution. The Credit Sprint app generates unlimited new versions with fresh numbers.

Problem 1.

In a population of 2000 in Hardy–Weinberg equilibrium, 320 individuals show the recessive phenotype. What is the frequency of the recessive allele (q)?

Show solution

q² = 320 ÷ 2000 = 0.16, so q = √0.16 = 0.4.

Problem 2.

In a population of 800 in Hardy–Weinberg equilibrium, 200 individuals show the recessive phenotype. What is the frequency of the recessive allele (q)?

Show solution

q² = 200 ÷ 800 = 0.25, so q = √0.25 = 0.5.

Problem 3.

In a population of 1000 in Hardy–Weinberg equilibrium, 10 individuals show the recessive phenotype. What is the frequency of the recessive allele (q)?

Show solution

q² = 10 ÷ 1000 = 0.01, so q = √0.01 = 0.1.

Problem 4.

In a population of 500 in Hardy–Weinberg equilibrium, 180 individuals show the recessive phenotype. What is the frequency of the recessive allele (q)?

Show solution

q² = 180 ÷ 500 = 0.36, so q = √0.36 = 0.6.

Problem 5.

In a population of 2000 in Hardy–Weinberg equilibrium, 500 individuals show the recessive phenotype. What is the frequency of the recessive allele (q)?

Show solution

q² = 500 ÷ 2000 = 0.25, so q = √0.25 = 0.5.

Problem 6.

In a population of 1000 in Hardy–Weinberg equilibrium, 40 individuals show the recessive phenotype. What is the frequency of the recessive allele (q)?

Show solution

q² = 40 ÷ 1000 = 0.04, so q = √0.04 = 0.2.