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Finding the Fourth Proportional to 642.30, 885.42 and 494.64

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Solution

The fourth proportional to 642.30, 885.42 and 494.64 is: 681.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.30 : 885.42 = 494.64 : x
  2. Step 2: Convert to fraction form
    642.30/885.42 = 494.64/x
  3. Step 3: Cross multiply
    642.30x = 885.42 × 494.64
  4. Step 4: Simplify right side
    642.30x = 437,964.15
  5. Step 5: Solve for x
    x = 437,964.15/642.30
  6. Step 6: Final answer
    x = 681.87

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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.