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Finding the Fourth Proportional to 342.78, 512.94 and 205.70

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Solution

The fourth proportional to 342.78, 512.94 and 205.70 is: 307.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.78 : 512.94 = 205.70 : x
  2. Step 2: Convert to fraction form
    342.78/512.94 = 205.70/x
  3. Step 3: Cross multiply
    342.78x = 512.94 × 205.70
  4. Step 4: Simplify right side
    342.78x = 105,511.76
  5. Step 5: Solve for x
    x = 105,511.76/342.78
  6. Step 6: Final answer
    x = 307.81

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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.