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Finding the Fourth Proportional to 123.80, 168.80 and 123.80

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Solution

The fourth proportional to 123.80, 168.80 and 123.80 is: 168.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    123.80 : 168.80 = 123.80 : x
  2. Step 2: Convert to fraction form
    123.80/168.80 = 123.80/x
  3. Step 3: Cross multiply
    123.80x = 168.80 × 123.80
  4. Step 4: Simplify right side
    123.80x = 20,897.44
  5. Step 5: Solve for x
    x = 20,897.44/123.80
  6. Step 6: Final answer
    x = 168.80

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.