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Finding the Fourth Proportional to 438.20, 657.18 and 129.98

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Solution

The fourth proportional to 438.20, 657.18 and 129.98 is: 194.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.20 : 657.18 = 129.98 : x
  2. Step 2: Convert to fraction form
    438.20/657.18 = 129.98/x
  3. Step 3: Cross multiply
    438.20x = 657.18 × 129.98
  4. Step 4: Simplify right side
    438.20x = 85,420.26
  5. Step 5: Solve for x
    x = 85,420.26/438.20
  6. Step 6: Final answer
    x = 194.93

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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.