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Finding the Fourth Proportional to 54.90, 82.26 and 39.78

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Solution

The fourth proportional to 54.90, 82.26 and 39.78 is: 59.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    54.90 : 82.26 = 39.78 : x
  2. Step 2: Convert to fraction form
    54.90/82.26 = 39.78/x
  3. Step 3: Cross multiply
    54.90x = 82.26 × 39.78
  4. Step 4: Simplify right side
    54.90x = 3,272.30
  5. Step 5: Solve for x
    x = 3,272.30/54.90
  6. Step 6: Final answer
    x = 59.60

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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.