要如何算 interest rate？Form 3 Maths Chapter 3

Question

请问要如何算 interest rate？

Answer 1

I = Prt 

RM 384 = RM 4000 x r/100 x 3
384 ➗3 = 4000 x r/100
128 = 40r 
128/40 = r
3.2 = r
r = 3.2 %

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