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Finding the Fourth Proportional to 88.72, 122.38 and 77.69

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Solution

The fourth proportional to 88.72, 122.38 and 77.69 is: 107.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.72 : 122.38 = 77.69 : x
  2. Step 2: Convert to fraction form
    88.72/122.38 = 77.69/x
  3. Step 3: Cross multiply
    88.72x = 122.38 × 77.69
  4. Step 4: Simplify right side
    88.72x = 9,507.81
  5. Step 5: Solve for x
    x = 9,507.81/88.72
  6. Step 6: Final answer
    x = 107.17

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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.