I have databases of people in countries, with sex, but the sex ratio of the databases don't always correspond with the actual sex ratio of the country.
I am looking for a formula to be able to multiply the sex that is under represented in the database, so it corresponds to the actual sex ratio of the country.
Sex ratios are presented as male:female.
Two examples where females are over represented:
**Qatar**
Sex ratio in database: 2.35
Actual sex ratio: 3.41
Males: 194,352
Females: 76,563
Total: 270,915
**Botswana**
Sex ratio in database: 0.89
Actual sex ratio: 1.04
Males: 176,790
Females: 203,742
Total: 380,532
An example where males are over represented:
**Sudan**
Sex ratio in database: 2.4
Actual sex ratio: 1.02
Male: 129,565
Female: 51,207
Total: 180,772
In the case of Qatar I want to be able to increase the males from 194,352 (which is a sex ratio of 2.35 males to females) to be in line with the actual sex ratio of the country (3.41).
This can be achieved with the sum:
194,352 × 1.345 = 261,403
This gives a ratio of 3.41 males to females with 261,403 : 76,563.
However, I can't find a way to arrive at the 1.345 number. Can anyone assist?
Your $2.35$ is not correct. $\frac{194352}{76563} \approx 2.538$. Then $\frac {3.41}{2.538} \approx 1.344$. You just need to divide the desired ratio by the existing ratio. Your other printed sex ratios also do not match the result of dividing males by females.