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									Re: Raymond borrowed $450 at 0% interest. If he pays back 0.5%									
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									01 Jul 2018, 14:07																	
							 
							
														
								Explanation
1% of $450 is $4.50, so 0.5% is $2.25. That’s the amount Raymond pays back every week.
Because he has paid back $18 in total, divide 18 by 2.25 to determine the total number of payments:
\(\frac{18}{2.25}= 8.\)
So Raymond has made 8 payments, once every 7 days. The payments themselves spread over only a 7-week period (in the same way that 2 payments spread over only a 1-week period). 
Raymond waited 1 week to begin repayment, however, so a total of 8 weeks, or 56 days, have passed since he borrowed the money.