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Finding the Fourth Proportional to 647.38, 893.19 and 385.21

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Solution

The fourth proportional to 647.38, 893.19 and 385.21 is: 531.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.38 : 893.19 = 385.21 : x
  2. Step 2: Convert to fraction form
    647.38/893.19 = 385.21/x
  3. Step 3: Cross multiply
    647.38x = 893.19 × 385.21
  4. Step 4: Simplify right side
    647.38x = 344,065.72
  5. Step 5: Solve for x
    x = 344,065.72/647.38
  6. Step 6: Final answer
    x = 531.47

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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.