First you would need to find out how many 9 payments of 58$ would be and that is 522. Then you would need to subtract the 522 and the 480 and your answer would be 42$ so the interest would be 42$
18/30 simplifies into 6/10 which then is put in decimal form of 0.6
So you move left to right like PEMDAS when it comes to adding or subtracting either or could go first and same thing applies with multiplying and dividing so for instance in this case
47*7=329
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329/9=36.5
Nine thousand, two hundred.
That painting would be 1 yard and 2 inches left over