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Finding the Fourth Proportional to 137.30, 204.68 and 121.81

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Solution

The fourth proportional to 137.30, 204.68 and 121.81 is: 181.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.30 : 204.68 = 121.81 : x
  2. Step 2: Convert to fraction form
    137.30/204.68 = 121.81/x
  3. Step 3: Cross multiply
    137.30x = 204.68 × 121.81
  4. Step 4: Simplify right side
    137.30x = 24,931.05
  5. Step 5: Solve for x
    x = 24,931.05/137.30
  6. Step 6: Final answer
    x = 181.59

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.