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Finding the Fourth Proportional to 840.20, 1,260.96 and 353

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Solution

The fourth proportional to 840.20, 1,260.96 and 353 is: 529.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.20 : 1,260.96 = 353 : x
  2. Step 2: Convert to fraction form
    840.20/1,260.96 = 353/x
  3. Step 3: Cross multiply
    840.20x = 1,260.96 × 353
  4. Step 4: Simplify right side
    840.20x = 445,118.88
  5. Step 5: Solve for x
    x = 445,118.88/840.20
  6. Step 6: Final answer
    x = 529.78

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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.