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Finding the Fourth Proportional to 581.40, 871.20 and 489.60

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Solution

The fourth proportional to 581.40, 871.20 and 489.60 is: 733.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    581.40 : 871.20 = 489.60 : x
  2. Step 2: Convert to fraction form
    581.40/871.20 = 489.60/x
  3. Step 3: Cross multiply
    581.40x = 871.20 × 489.60
  4. Step 4: Simplify right side
    581.40x = 426,539.52
  5. Step 5: Solve for x
    x = 426,539.52/581.40
  6. Step 6: Final answer
    x = 733.64

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.