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Finding the Fourth Proportional to 137.70, 207.36 and 129.60

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Solution

The fourth proportional to 137.70, 207.36 and 129.60 is: 195.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.70 : 207.36 = 129.60 : x
  2. Step 2: Convert to fraction form
    137.70/207.36 = 129.60/x
  3. Step 3: Cross multiply
    137.70x = 207.36 × 129.60
  4. Step 4: Simplify right side
    137.70x = 26,873.86
  5. Step 5: Solve for x
    x = 26,873.86/137.70
  6. Step 6: Final answer
    x = 195.16

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.