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Finding the Fourth Proportional to 131.25, 181.11 and 78.79

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Solution

The fourth proportional to 131.25, 181.11 and 78.79 is: 108.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    131.25 : 181.11 = 78.79 : x
  2. Step 2: Convert to fraction form
    131.25/181.11 = 78.79/x
  3. Step 3: Cross multiply
    131.25x = 181.11 × 78.79
  4. Step 4: Simplify right side
    131.25x = 14,268.75
  5. Step 5: Solve for x
    x = 14,268.75/131.25
  6. Step 6: Final answer
    x = 108.71

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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.