If jake can complete a job in 1 hour 30 minutes and his friend Harry can complete the same job in half the time, how long will it take to complete the job if they work together?

Answer:if they work together, it will take them 0.5 hours or 30 minutes

Step-by-step explanation:

jake can complete a job in 1 hour 30 minutes or 1.5 hours. This means that his unit rate is 1/1.5

his friend Harry can complete the same job in half the time. This means that Harry can complete the same job in 0.75 hours. His unit rate of working would be 1/0.75.

Since both of them work simultaneously at their individual rates, then, Their unit rates are additive. Assuming by working together, it took them t hours to finish the work. This means that their combined unit rate would be 1/t. Therefore,

1/1.5 + 1/0.75 = 1/t

1/t = 2

2t = 1

t = 1/2 = 0.5 hours or 30 minutes