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Finding the Fourth Proportional to 691.90, 954.81 and 397.18

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Solution

The fourth proportional to 691.90, 954.81 and 397.18 is: 548.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    691.90 : 954.81 = 397.18 : x
  2. Step 2: Convert to fraction form
    691.90/954.81 = 397.18/x
  3. Step 3: Cross multiply
    691.90x = 954.81 × 397.18
  4. Step 4: Simplify right side
    691.90x = 379,231.44
  5. Step 5: Solve for x
    x = 379,231.44/691.90
  6. Step 6: Final answer
    x = 548.10

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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.