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Finding the Fourth Proportional to 101.78, 152.72 and 40.90

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Solution

The fourth proportional to 101.78, 152.72 and 40.90 is: 61.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.78 : 152.72 = 40.90 : x
  2. Step 2: Convert to fraction form
    101.78/152.72 = 40.90/x
  3. Step 3: Cross multiply
    101.78x = 152.72 × 40.90
  4. Step 4: Simplify right side
    101.78x = 6,245.97
  5. Step 5: Solve for x
    x = 6,245.97/101.78
  6. Step 6: Final answer
    x = 61.37

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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.