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Finding the Fourth Proportional to 88.78, 122.16 and 77.89

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Solution

The fourth proportional to 88.78, 122.16 and 77.89 is: 107.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.78 : 122.16 = 77.89 : x
  2. Step 2: Convert to fraction form
    88.78/122.16 = 77.89/x
  3. Step 3: Cross multiply
    88.78x = 122.16 × 77.89
  4. Step 4: Simplify right side
    88.78x = 9,515.04
  5. Step 5: Solve for x
    x = 9,515.04/88.78
  6. Step 6: Final answer
    x = 107.18

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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.