Question

The graphs below are based on government data on unemployment for 2017.

Answer 1

You already got the first two questions right: the group with the highest number of people unemployed / unemployment rate is the one with the highest bar in the respective histogram.

The two graph are related in this sense: take the first age group as reference. We know that 700 people from 16 to 19 are unemployed, and that those people represent 14% of the population, then we know that the 14% of the population between 16 and 19 is 700.

We can deduce that, if x is the number of people between 16 and 19, we have

$\dfrac{14}{100}x=700 \iff \dfrac{7}{50}x=700 \iff \dfrac{x}{50}=100 \iff x=5000$

So, by the relation between the two graphs, we can deduce the total population for each age group.