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Finding the Fourth Proportional to 438.91, 658.45 and 130.78

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Solution

The fourth proportional to 438.91, 658.45 and 130.78 is: 196.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.91 : 658.45 = 130.78 : x
  2. Step 2: Convert to fraction form
    438.91/658.45 = 130.78/x
  3. Step 3: Cross multiply
    438.91x = 658.45 × 130.78
  4. Step 4: Simplify right side
    438.91x = 86,113.93
  5. Step 5: Solve for x
    x = 86,113.93/438.91
  6. Step 6: Final answer
    x = 196.20

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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.