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Finding the Fourth Proportional to 642.60, 963.42 and 459.88

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Solution

The fourth proportional to 642.60, 963.42 and 459.88 is: 689.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.60 : 963.42 = 459.88 : x
  2. Step 2: Convert to fraction form
    642.60/963.42 = 459.88/x
  3. Step 3: Cross multiply
    642.60x = 963.42 × 459.88
  4. Step 4: Simplify right side
    642.60x = 443,057.59
  5. Step 5: Solve for x
    x = 443,057.59/642.60
  6. Step 6: Final answer
    x = 689.48

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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.