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Finding the Fourth Proportional to 668.39, 921.02 and 665.82

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Solution

The fourth proportional to 668.39, 921.02 and 665.82 is: 917.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.39 : 921.02 = 665.82 : x
  2. Step 2: Convert to fraction form
    668.39/921.02 = 665.82/x
  3. Step 3: Cross multiply
    668.39x = 921.02 × 665.82
  4. Step 4: Simplify right side
    668.39x = 613,230.21
  5. Step 5: Solve for x
    x = 613,230.21/668.39
  6. Step 6: Final answer
    x = 917.48

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.