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Finding the Fourth Proportional to 105.80, 158.68 and 40.78

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Solution

The fourth proportional to 105.80, 158.68 and 40.78 is: 61.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    105.80 : 158.68 = 40.78 : x
  2. Step 2: Convert to fraction form
    105.80/158.68 = 40.78/x
  3. Step 3: Cross multiply
    105.80x = 158.68 × 40.78
  4. Step 4: Simplify right side
    105.80x = 6,470.97
  5. Step 5: Solve for x
    x = 6,470.97/105.80
  6. Step 6: Final answer
    x = 61.16

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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.