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Finding the Fourth Proportional to 608.90, 840.47 and 347.09

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Solution

The fourth proportional to 608.90, 840.47 and 347.09 is: 479.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    608.90 : 840.47 = 347.09 : x
  2. Step 2: Convert to fraction form
    608.90/840.47 = 347.09/x
  3. Step 3: Cross multiply
    608.90x = 840.47 × 347.09
  4. Step 4: Simplify right side
    608.90x = 291,712.79
  5. Step 5: Solve for x
    x = 291,712.79/608.90
  6. Step 6: Final answer
    x = 479.09

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.