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Finding the Fourth Proportional to 668.40, 1,003.74 and 633.78

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Solution

The fourth proportional to 668.40, 1,003.74 and 633.78 is: 951.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.40 : 1,003.74 = 633.78 : x
  2. Step 2: Convert to fraction form
    668.40/1,003.74 = 633.78/x
  3. Step 3: Cross multiply
    668.40x = 1,003.74 × 633.78
  4. Step 4: Simplify right side
    668.40x = 636,150.34
  5. Step 5: Solve for x
    x = 636,150.34/668.40
  6. Step 6: Final answer
    x = 951.75

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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.