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Finding the Fourth Proportional to 105.78, 158.37 and 87.66

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Solution

The fourth proportional to 105.78, 158.37 and 87.66 is: 131.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    105.78 : 158.37 = 87.66 : x
  2. Step 2: Convert to fraction form
    105.78/158.37 = 87.66/x
  3. Step 3: Cross multiply
    105.78x = 158.37 × 87.66
  4. Step 4: Simplify right side
    105.78x = 13,882.71
  5. Step 5: Solve for x
    x = 13,882.71/105.78
  6. Step 6: Final answer
    x = 131.24

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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.