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Finding the Fourth Proportional to 155.64, 213.87 and 129.72

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Solution

The fourth proportional to 155.64, 213.87 and 129.72 is: 178.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.64 : 213.87 = 129.72 : x
  2. Step 2: Convert to fraction form
    155.64/213.87 = 129.72/x
  3. Step 3: Cross multiply
    155.64x = 213.87 × 129.72
  4. Step 4: Simplify right side
    155.64x = 27,743.22
  5. Step 5: Solve for x
    x = 27,743.22/155.64
  6. Step 6: Final answer
    x = 178.25

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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.