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Finding the Fourth Proportional to 135.78, 187.34 and 108.12

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Solution

The fourth proportional to 135.78, 187.34 and 108.12 is: 149.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    135.78 : 187.34 = 108.12 : x
  2. Step 2: Convert to fraction form
    135.78/187.34 = 108.12/x
  3. Step 3: Cross multiply
    135.78x = 187.34 × 108.12
  4. Step 4: Simplify right side
    135.78x = 20,255.20
  5. Step 5: Solve for x
    x = 20,255.20/135.78
  6. Step 6: Final answer
    x = 149.18

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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.