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Finding the Fourth Proportional to 840.20, 1,260.32 and 320.46

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Solution

The fourth proportional to 840.20, 1,260.32 and 320.46 is: 480.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.20 : 1,260.32 = 320.46 : x
  2. Step 2: Convert to fraction form
    840.20/1,260.32 = 320.46/x
  3. Step 3: Cross multiply
    840.20x = 1,260.32 × 320.46
  4. Step 4: Simplify right side
    840.20x = 403,882.15
  5. Step 5: Solve for x
    x = 403,882.15/840.20
  6. Step 6: Final answer
    x = 480.70

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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.