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Finding the Fourth Proportional to 77.52, 107.01 and 61.21

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Solution

The fourth proportional to 77.52, 107.01 and 61.21 is: 84.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.52 : 107.01 = 61.21 : x
  2. Step 2: Convert to fraction form
    77.52/107.01 = 61.21/x
  3. Step 3: Cross multiply
    77.52x = 107.01 × 61.21
  4. Step 4: Simplify right side
    77.52x = 6,550.08
  5. Step 5: Solve for x
    x = 6,550.08/77.52
  6. Step 6: Final answer
    x = 84.50

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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.