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Finding the Fourth Proportional to 66.35, 99.06 and 54.78

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Solution

The fourth proportional to 66.35, 99.06 and 54.78 is: 81.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.35 : 99.06 = 54.78 : x
  2. Step 2: Convert to fraction form
    66.35/99.06 = 54.78/x
  3. Step 3: Cross multiply
    66.35x = 99.06 × 54.78
  4. Step 4: Simplify right side
    66.35x = 5,426.45
  5. Step 5: Solve for x
    x = 5,426.45/66.35
  6. Step 6: Final answer
    x = 81.79

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.