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Finding the Fourth Proportional to 154.65, 231.63 and 81.30

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Solution

The fourth proportional to 154.65, 231.63 and 81.30 is: 121.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    154.65 : 231.63 = 81.30 : x
  2. Step 2: Convert to fraction form
    154.65/231.63 = 81.30/x
  3. Step 3: Cross multiply
    154.65x = 231.63 × 81.30
  4. Step 4: Simplify right side
    154.65x = 18,831.52
  5. Step 5: Solve for x
    x = 18,831.52/154.65
  6. Step 6: Final answer
    x = 121.77

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.