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Finding the Fourth Proportional to 77.30, 106.81 and 63.48

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Solution

The fourth proportional to 77.30, 106.81 and 63.48 is: 87.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.30 : 106.81 = 63.48 : x
  2. Step 2: Convert to fraction form
    77.30/106.81 = 63.48/x
  3. Step 3: Cross multiply
    77.30x = 106.81 × 63.48
  4. Step 4: Simplify right side
    77.30x = 6,779.82
  5. Step 5: Solve for x
    x = 6,779.82/77.30
  6. Step 6: Final answer
    x = 87.71

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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.