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Finding the Fourth Proportional to 670.91, 1,006.21 and 378.54

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Solution

The fourth proportional to 670.91, 1,006.21 and 378.54 is: 567.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    670.91 : 1,006.21 = 378.54 : x
  2. Step 2: Convert to fraction form
    670.91/1,006.21 = 378.54/x
  3. Step 3: Cross multiply
    670.91x = 1,006.21 × 378.54
  4. Step 4: Simplify right side
    670.91x = 380,890.73
  5. Step 5: Solve for x
    x = 380,890.73/670.91
  6. Step 6: Final answer
    x = 567.72

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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.