Find the principal. SHOW ALL WORK to receive FULL CREDIT. I=P∙r∙t

Interest earned: $45

Principal: ?

Interest rate: 3%

Time: 5 months

answer:  

\boxed {\frac{1}{5}}  

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solution-

60 *   \frac{1}{5}   = 12

90 * \frac{1}{5} = 18

75 * \frac{1}{5} = 15

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hence, the answer would be \boxed {\frac{1}{5}}