Hardy-Weinberg Blog

Step 1: Identify your given values.

·  Population: 1000

·  q2: .731

Step 2: Take the square root of q2 in order to solve for q.

·  √q2 = q

·  √.731 = .85

Step 3: Since the Hardy-Weinberg rule says that the sum of p and q is 1, then to find the value of p,
subtract q from 1. After that, you
square the p value to find the p2 value.

·  1-q=p

·  1-.85=.15

·  p2=.0225

Step 4: Once you have the p,q, q2, and p2 values, finding the 2pq value 
is simple. What you have to do is multiple p times q and them multiply that product by 2.

(p x q)(2) = 2pq
(.15 x .85)(2) = .255

Step 5: To find the number of  individuals in the population, you multiply each  of the values which stand for an individual (p2, q2, 2pq) bythe total number of individuals in the population.

(.255)(1000) = 255 heterogeneous individuals

(.731)(1000) = 731 homogeneous recessive individuals

(.0225)(1000) = about 23 [when rounded] homogeneous dominant individuals.

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