Using the together rate, it is found that it will take 18 hours for Erick to build the garden box himself.
<h3>What is the together rate?</h3>
The together rate is given by the sum of each separate rate.
In this problem, the rates are given as follows:
Hence:


x = 18.
Hence, it will take 18 hours for Erick to build the garden box himself.
More can be learned about the together rate at brainly.com/question/25159431
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