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Finding the Fourth Proportional to 130.18, 178.82 and 128.38

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Solution

The fourth proportional to 130.18, 178.82 and 128.38 is: 176.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.18 : 178.82 = 128.38 : x
  2. Step 2: Convert to fraction form
    130.18/178.82 = 128.38/x
  3. Step 3: Cross multiply
    130.18x = 178.82 × 128.38
  4. Step 4: Simplify right side
    130.18x = 22,956.91
  5. Step 5: Solve for x
    x = 22,956.91/130.18
  6. Step 6: Final answer
    x = 176.35

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.