Answer:
the last one is 21.
for number 5 the number of workers with minimum wage are 24 and also 15 percent of the whole company i.e 15/100 × whole company's employees. after doing the calculation you can get the answer.
For 9 we know that Alice's working experience is 8 years plus Kathy's experience and we also got to know that the working experience ok Kathy is half of working experience of sheila i.e 5 years so we just add it up and got the answer.