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Finding the Fourth Proportional to 638.69, 882.66 and 498.66

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Solution

The fourth proportional to 638.69, 882.66 and 498.66 is: 689.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.69 : 882.66 = 498.66 : x
  2. Step 2: Convert to fraction form
    638.69/882.66 = 498.66/x
  3. Step 3: Cross multiply
    638.69x = 882.66 × 498.66
  4. Step 4: Simplify right side
    638.69x = 440,145.80
  5. Step 5: Solve for x
    x = 440,145.80/638.69
  6. Step 6: Final answer
    x = 689.14

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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.