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Finding the Fourth Proportional to 153.90, 211.34 and 129.30

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Solution

The fourth proportional to 153.90, 211.34 and 129.30 is: 177.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    153.90 : 211.34 = 129.30 : x
  2. Step 2: Convert to fraction form
    153.90/211.34 = 129.30/x
  3. Step 3: Cross multiply
    153.90x = 211.34 × 129.30
  4. Step 4: Simplify right side
    153.90x = 27,325.79
  5. Step 5: Solve for x
    x = 27,325.79/153.90
  6. Step 6: Final answer
    x = 177.56

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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.