3rd Class math is about the same as High School, 2nd Class is just a bit higher. I strongly suggest you go for 2nd Class Applied Mechanics, the math standard is just a wee bit tougher than 3 Maths, but when you pass 2APM , you'll be exempted 3 Math and 3 APM. Saves you $55 and the hassle of writing 3 exams!
I suggest you get Reeds Applied Mechanics for Marine Engineers. When you can knock off most of the examples in the book, you're ready for 2nd Applied Mechanics. Don't do the ones marked with a 'f', they're for 1st Class, you can't write that until you have 2nd Class.
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