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Finding the Fourth Proportional to 668.10, 1,000.89 and 378.66

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Solution

The fourth proportional to 668.10, 1,000.89 and 378.66 is: 567.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.10 : 1,000.89 = 378.66 : x
  2. Step 2: Convert to fraction form
    668.10/1,000.89 = 378.66/x
  3. Step 3: Cross multiply
    668.10x = 1,000.89 × 378.66
  4. Step 4: Simplify right side
    668.10x = 378,997.01
  5. Step 5: Solve for x
    x = 378,997.01/668.10
  6. Step 6: Final answer
    x = 567.28

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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.