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Finding the Fourth Proportional to 840.31, 1,260.90 and 347.08

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Solution

The fourth proportional to 840.31, 1,260.90 and 347.08 is: 520.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.31 : 1,260.90 = 347.08 : x
  2. Step 2: Convert to fraction form
    840.31/1,260.90 = 347.08/x
  3. Step 3: Cross multiply
    840.31x = 1,260.90 × 347.08
  4. Step 4: Simplify right side
    840.31x = 437,625.13
  5. Step 5: Solve for x
    x = 437,625.13/840.31
  6. Step 6: Final answer
    x = 520.79

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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.