Using proportions, it is found that it will take him 22.5 hours to walk the 45 dogs.
<h3>What is a proportion?</h3>
A proportion is a fraction of a total amount, and the measures are related using a rule of three. Due to this, relations between variables, either direct or inverse proportional, can be built to find the desired measures in the problem.
He walks 3 dogs in 1 hour and 30 minutes, we means that the time in hours it takes for him to walk a dog is:
t = 1.5/3 = 0.5 hours.
Hence the time it will take him to walk 45 dogs is given by:
45 x 0.5 = 22.5 hours.
More can be learned about proportions at brainly.com/question/24372153
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