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Finding the Fourth Proportional to 611.55, 915.17 and 419.31

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Solution

The fourth proportional to 611.55, 915.17 and 419.31 is: 627.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    611.55 : 915.17 = 419.31 : x
  2. Step 2: Convert to fraction form
    611.55/915.17 = 419.31/x
  3. Step 3: Cross multiply
    611.55x = 915.17 × 419.31
  4. Step 4: Simplify right side
    611.55x = 383,737.84
  5. Step 5: Solve for x
    x = 383,737.84/611.55
  6. Step 6: Final answer
    x = 627.48

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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.