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Finding the Fourth Proportional to 153.05, 211.17 and 87.55

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Solution

The fourth proportional to 153.05, 211.17 and 87.55 is: 120.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    153.05 : 211.17 = 87.55 : x
  2. Step 2: Convert to fraction form
    153.05/211.17 = 87.55/x
  3. Step 3: Cross multiply
    153.05x = 211.17 × 87.55
  4. Step 4: Simplify right side
    153.05x = 18,487.93
  5. Step 5: Solve for x
    x = 18,487.93/153.05
  6. Step 6: Final answer
    x = 120.80

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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.