In country Z, 10% of the people do not have a university dip

Setting up a matrix is how I solve this one.


Diploma No Diploma Totals
Job of Choice w/Diploma
Job of Choice w/o Diploma = 10%
Job of Choice Total = 40%
Not Job of Choice with Diploma =.25X
Not Job of Choice w/o Diploma= .75X
Total Not Job of Choice = X
Total with Diploma
Total without Diploma
Total citizen = 100
If 40% of people have their job of choice, then 60% of people do NOT have their job of choice. 25% of 60% = 15%. We can also see that 30% of the people have their job of choice and a diploma (40%-10%=30%). 30% + 15% = 45%. Therefore 45% of the people in Country Z have a diploma.

this can be done using a matrix set as in the attached.

out of 100, 40 have desired jobs and 60 don't have.
out of 60,25% have university degree = 0.25 * 60 = 15

out of 40,10 do not have university degree but have desired job.
thus 30 have desired job as well as university degree

hence total = 30 + 15 = 45 have university degree.

Can someone help me to understand why do we do 25 % of 60 instead of just adding 30 +25??

Because the stem says that "25% of the people who do not have the job have a university diploma", not that "25% have a university diploma". 60% do NOT have the job, thus 25% of this group have a university diploma.

Hope it's clear.

Bunuel, How would you solve this problem via equations??

solved it through double matrix

Is it wrong to assume that some proportion of people in country have neither a job nor a diploma?

Why not 10% of the 40%? Why we have directly used 10% in job and no University diploma?





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