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Finding the Fourth Proportional to 142.05, 213.08 and 115.05

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Solution

The fourth proportional to 142.05, 213.08 and 115.05 is: 172.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    142.05 : 213.08 = 115.05 : x
  2. Step 2: Convert to fraction form
    142.05/213.08 = 115.05/x
  3. Step 3: Cross multiply
    142.05x = 213.08 × 115.05
  4. Step 4: Simplify right side
    142.05x = 24,514.85
  5. Step 5: Solve for x
    x = 24,514.85/142.05
  6. Step 6: Final answer
    x = 172.58

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.