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Finding the Fourth Proportional to 66.20, 99.10 and 51.80

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Solution

The fourth proportional to 66.20, 99.10 and 51.80 is: 77.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.20 : 99.10 = 51.80 : x
  2. Step 2: Convert to fraction form
    66.20/99.10 = 51.80/x
  3. Step 3: Cross multiply
    66.20x = 99.10 × 51.80
  4. Step 4: Simplify right side
    66.20x = 5,133.38
  5. Step 5: Solve for x
    x = 5,133.38/66.20
  6. Step 6: Final answer
    x = 77.54

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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.