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Finding the Fourth Proportional to 642.59, 887.11 and 494.90

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Solution

The fourth proportional to 642.59, 887.11 and 494.90 is: 683.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.59 : 887.11 = 494.90 : x
  2. Step 2: Convert to fraction form
    642.59/887.11 = 494.90/x
  3. Step 3: Cross multiply
    642.59x = 887.11 × 494.90
  4. Step 4: Simplify right side
    642.59x = 439,026.30
  5. Step 5: Solve for x
    x = 439,026.30/642.59
  6. Step 6: Final answer
    x = 683.22

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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.