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Finding the Fourth Proportional to 618.60, 854.10 and 398.12

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Solution

The fourth proportional to 618.60, 854.10 and 398.12 is: 549.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.60 : 854.10 = 398.12 : x
  2. Step 2: Convert to fraction form
    618.60/854.10 = 398.12/x
  3. Step 3: Cross multiply
    618.60x = 854.10 × 398.12
  4. Step 4: Simplify right side
    618.60x = 340,034.29
  5. Step 5: Solve for x
    x = 340,034.29/618.60
  6. Step 6: Final answer
    x = 549.68

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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.