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Finding the Fourth Proportional to 77.52, 107.04 and 61.28

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Solution

The fourth proportional to 77.52, 107.04 and 61.28 is: 84.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.52 : 107.04 = 61.28 : x
  2. Step 2: Convert to fraction form
    77.52/107.04 = 61.28/x
  3. Step 3: Cross multiply
    77.52x = 107.04 × 61.28
  4. Step 4: Simplify right side
    77.52x = 6,559.41
  5. Step 5: Solve for x
    x = 6,559.41/77.52
  6. Step 6: Final answer
    x = 84.62

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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.