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Finding the Fourth Proportional to 206.50, 309.77 and 103.78

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Solution

The fourth proportional to 206.50, 309.77 and 103.78 is: 155.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    206.50 : 309.77 = 103.78 : x
  2. Step 2: Convert to fraction form
    206.50/309.77 = 103.78/x
  3. Step 3: Cross multiply
    206.50x = 309.77 × 103.78
  4. Step 4: Simplify right side
    206.50x = 32,148.77
  5. Step 5: Solve for x
    x = 32,148.77/206.50
  6. Step 6: Final answer
    x = 155.68

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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.