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Finding the Fourth Proportional to 77.52, 107.02 and 61.20

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Solution

The fourth proportional to 77.52, 107.02 and 61.20 is: 84.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.52 : 107.02 = 61.20 : x
  2. Step 2: Convert to fraction form
    77.52/107.02 = 61.20/x
  3. Step 3: Cross multiply
    77.52x = 107.02 × 61.20
  4. Step 4: Simplify right side
    77.52x = 6,549.62
  5. Step 5: Solve for x
    x = 6,549.62/77.52
  6. Step 6: Final answer
    x = 84.49

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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.