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Finding the Fourth Proportional to 619.39, 854.31 and 386.38

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Solution

The fourth proportional to 619.39, 854.31 and 386.38 is: 532.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.39 : 854.31 = 386.38 : x
  2. Step 2: Convert to fraction form
    619.39/854.31 = 386.38/x
  3. Step 3: Cross multiply
    619.39x = 854.31 × 386.38
  4. Step 4: Simplify right side
    619.39x = 330,088.30
  5. Step 5: Solve for x
    x = 330,088.30/619.39
  6. Step 6: Final answer
    x = 532.92

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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.