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Finding the Fourth Proportional to 619.68, 854.72 and 398.42

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Solution

The fourth proportional to 619.68, 854.72 and 398.42 is: 549.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.68 : 854.72 = 398.42 : x
  2. Step 2: Convert to fraction form
    619.68/854.72 = 398.42/x
  3. Step 3: Cross multiply
    619.68x = 854.72 × 398.42
  4. Step 4: Simplify right side
    619.68x = 340,537.69
  5. Step 5: Solve for x
    x = 340,537.69/619.68
  6. Step 6: Final answer
    x = 549.54

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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.