How to change 54% to a decimal number

Which point-slope form equation represents a line that passes through (3,-2) with a slope of -4/5

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In the next 10 month, colin wants to save $900 for his vacation. he plans to save $75 each of the first 8 months. how much must he save each of the last 2 months in order to meet his goal if he saves the same amount each month ?