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Finding the Fourth Proportional to 102.02, 140.78 and 77.41

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Solution

The fourth proportional to 102.02, 140.78 and 77.41 is: 106.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    102.02 : 140.78 = 77.41 : x
  2. Step 2: Convert to fraction form
    102.02/140.78 = 77.41/x
  3. Step 3: Cross multiply
    102.02x = 140.78 × 77.41
  4. Step 4: Simplify right side
    102.02x = 10,897.62
  5. Step 5: Solve for x
    x = 10,897.62/102.02
  6. Step 6: Final answer
    x = 106.82

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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.