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Finding the Fourth Proportional to 642.14, 885.92 and 421.22

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Solution

The fourth proportional to 642.14, 885.92 and 421.22 is: 581.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.14 : 885.92 = 421.22 : x
  2. Step 2: Convert to fraction form
    642.14/885.92 = 421.22/x
  3. Step 3: Cross multiply
    642.14x = 885.92 × 421.22
  4. Step 4: Simplify right side
    642.14x = 373,167.22
  5. Step 5: Solve for x
    x = 373,167.22/642.14
  6. Step 6: Final answer
    x = 581.13

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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.