Joe earned $140 for working 20 hours
To determine the value of a single unit from a specified multiple, use the unitary technique. How to determine the value of one pen, for instance, if the cost of 40 pens is Rs. 400. The unitary approach can be used to complete it. Additionally, after determining the value of a single unit, we can multiply that value by the number of units needed to determine the value of the additional units. The concept of ratio and proportion is mostly applied using this way.
Joe worked 14 hours and earned = $119
Joe worked for 1 hour and earned = $ 119/ 14
Joe worked for 20 hours and earned = $ 119/ 14 x 20
= 4140
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