Biology: phenotype, genotype and allele frequencies?

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1) Population of mice has dominant black and recessive tan coat color. A sample of the population yields 573 black and 190 tan mice. Determine the genotype, phenotype and allele frequencies.

2) You find a nearby population of mice with 103 and 88 tan mice. Is this population in equilibrium with the other? Explain why/ why not. If the population is distinct, how may this have come about?

For both questions, explanations and calculations would be helpful
 
for the first question. phenotype is what is looks like visually, genotype is what the genes look like and alleles are the individuals not in groups.

So the determining phenotype frequency is easy bc you have 190 and 573. just take a fraction of each. 190 / (190 + 573) is the recessive freq. and 573 / (190 + 573) is the dominate freq. of the phenotype.
And, for question one, im assuming that it is at equilibrium: meaning: 1AA + 2Aa + 1aa. Therefore the genotype of the dominate is the only trouble bc we know that aa is the 190 recessive. so just take (2/3) x 573 should give you the freq. of Aa. The 2/3rds is because there are twice as many heterozygous dominate as there are homo dominate. so the genotype freq. is thus: AA freq. = ((1/3) * 573) / (573 + 190). Aa freq. = ((2/3) * 573) / (573 + 190) and aa freq. = 190 / (573 + 190). (this is the only one that is the same as the phenotype freq. For allele freqency you just count the number of A's and a's and just divide by the total number of alleles. this should be easy now that youu know all the genotypes.

For question 2... In order to have equilibrium : 1AA - 2Aa - 1aa the dominate phenotype freq. needs to be 3 times as large as the recessive phenotype freq. But its not in this case. 88 * 3 does not equal 103. And i dont know what it means by the last part in question 2. Sorry. i hope this helps.
 
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