XYZ
When you took your exam you should certainly have been aware of the equation:
SAT = (TAT / (1 +(0.2 x k x Mach no squared))
It has always been part of the syllabus.
Past exams have often required students to identify the correct equation, but have rarely if ever required them to use it.
If the question posted in this string is a real JAR Instruments exam question then either there is a simple method of solving it using the CRP5, or else the CAA have xepanded their question bank and now require use of the equation. This is in line with their poilicy of trying to prevent students from passing simply by memorising the answers to feedback questions.