Update instructions.md (#2622)

Change wording to clarify that there are 22 billable days per month and the days given for each project are all billable days

Author: sparky9043

exercises/concept/freelancer-rates/.docs/instructions.md

@@ -36,8 +36,8 @@ daysInBudget(20000, 89);
 
 Often, the freelancer's clients hire them for projects spanning over multiple months.
 In these cases, the freelancer decides to offer a discount for every full month, and the remaining days are billed at day rate.
-**_Every month has 22 billable days._**
-Help them estimate their cost for such projects, given an hourly rate, the number of days the project spans, and a monthly discount rate.
+Your excellent work-life balance means that you only work 22 days in each calendar month, so **_every month has 22 billable days._**
+Help them estimate their cost for such projects, given an hourly rate, the number of billable days the project contains, and a monthly discount rate.
 The discount is always passed as a number, where `42%` becomes `0.42`. The result _must_ be **rounded up** to the nearest whole number.
 
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