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Finding the Fourth Proportional to 646.38, 971.19 and 415.40

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Solution

The fourth proportional to 646.38, 971.19 and 415.40 is: 624.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.38 : 971.19 = 415.40 : x
  2. Step 2: Convert to fraction form
    646.38/971.19 = 415.40/x
  3. Step 3: Cross multiply
    646.38x = 971.19 × 415.40
  4. Step 4: Simplify right side
    646.38x = 403,427.47
  5. Step 5: Solve for x
    x = 403,427.47/646.38
  6. Step 6: Final answer
    x = 624.13

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.