Find the formula steps of this problem Take a 30 cm long rectangular iron sheet, cut out a square iron sheet with a side length of 5 cm on each of the four corners, and weld a long uncovered rectangular iron box with a volume of 1500 cubic cm. Find out the width of the original rectangular iron sheet

Let the width be xcm
Then (X-10) (30-10) × 5 = 1500
100x-1000=1500
100x=2500
x=25(cm)

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