Explanation
One third of 84 is \(84 \times 1 / 3=84 \div 3=28\). 28 people 25 years old or younger applied for the job. Two seventh of 84 is \(84 \times 2 / 7=2 \times 84 \div 7=24\). 24 people who were at least 50 years old applied for the job. 84 - 28 - 24 = 32. 32 people applied for the job who were between 25 and 50.