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Finding the Fourth Proportional to 256.20, 383.90 and 205.17

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Solution

The fourth proportional to 256.20, 383.90 and 205.17 is: 307.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.20 : 383.90 = 205.17 : x
  2. Step 2: Convert to fraction form
    256.20/383.90 = 205.17/x
  3. Step 3: Cross multiply
    256.20x = 383.90 × 205.17
  4. Step 4: Simplify right side
    256.20x = 78,763.74
  5. Step 5: Solve for x
    x = 78,763.74/256.20
  6. Step 6: Final answer
    x = 307.43

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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.