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Finding the Fourth Proportional to 131.79, 181.76 and 100.65

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Solution

The fourth proportional to 131.79, 181.76 and 100.65 is: 138.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    131.79 : 181.76 = 100.65 : x
  2. Step 2: Convert to fraction form
    131.79/181.76 = 100.65/x
  3. Step 3: Cross multiply
    131.79x = 181.76 × 100.65
  4. Step 4: Simplify right side
    131.79x = 18,293.81
  5. Step 5: Solve for x
    x = 18,293.81/131.79
  6. Step 6: Final answer
    x = 138.81

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.