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Finding the Fourth Proportional to 222.61, 307.21 and 129.38

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Solution

The fourth proportional to 222.61, 307.21 and 129.38 is: 178.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    222.61 : 307.21 = 129.38 : x
  2. Step 2: Convert to fraction form
    222.61/307.21 = 129.38/x
  3. Step 3: Cross multiply
    222.61x = 307.21 × 129.38
  4. Step 4: Simplify right side
    222.61x = 39,746.83
  5. Step 5: Solve for x
    x = 39,746.83/222.61
  6. Step 6: Final answer
    x = 178.55

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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.