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Finding the Fourth Proportional to 137.87, 206.80 and 56.71

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Solution

The fourth proportional to 137.87, 206.80 and 56.71 is: 85.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.87 : 206.80 = 56.71 : x
  2. Step 2: Convert to fraction form
    137.87/206.80 = 56.71/x
  3. Step 3: Cross multiply
    137.87x = 206.80 × 56.71
  4. Step 4: Simplify right side
    137.87x = 11,727.96
  5. Step 5: Solve for x
    x = 11,727.96/137.87
  6. Step 6: Final answer
    x = 85.07

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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.