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Finding the Fourth Proportional to 54.60, 81.78 and 43.80

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Solution

The fourth proportional to 54.60, 81.78 and 43.80 is: 65.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    54.60 : 81.78 = 43.80 : x
  2. Step 2: Convert to fraction form
    54.60/81.78 = 43.80/x
  3. Step 3: Cross multiply
    54.60x = 81.78 × 43.80
  4. Step 4: Simplify right side
    54.60x = 3,581.96
  5. Step 5: Solve for x
    x = 3,581.96/54.60
  6. Step 6: Final answer
    x = 65.60

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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.