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Finding the Fourth Proportional to 136.80, 208.80 and 136.80

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Solution

The fourth proportional to 136.80, 208.80 and 136.80 is: 208.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    136.80 : 208.80 = 136.80 : x
  2. Step 2: Convert to fraction form
    136.80/208.80 = 136.80/x
  3. Step 3: Cross multiply
    136.80x = 208.80 × 136.80
  4. Step 4: Simplify right side
    136.80x = 28,563.84
  5. Step 5: Solve for x
    x = 28,563.84/136.80
  6. Step 6: Final answer
    x = 208.80

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Why These Related Problems?

These problems maintain the same ratio (1.53) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.