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Finding the Fourth Proportional to 50.70, 69.80 and 39.81

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Solution

The fourth proportional to 50.70, 69.80 and 39.81 is: 54.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    50.70 : 69.80 = 39.81 : x
  2. Step 2: Convert to fraction form
    50.70/69.80 = 39.81/x
  3. Step 3: Cross multiply
    50.70x = 69.80 × 39.81
  4. Step 4: Simplify right side
    50.70x = 2,778.54
  5. Step 5: Solve for x
    x = 2,778.54/50.70
  6. Step 6: Final answer
    x = 54.80

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.