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Finding the Fourth Proportional to 668.02, 921.75 and 388.30

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Solution

The fourth proportional to 668.02, 921.75 and 388.30 is: 535.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.02 : 921.75 = 388.30 : x
  2. Step 2: Convert to fraction form
    668.02/921.75 = 388.30/x
  3. Step 3: Cross multiply
    668.02x = 921.75 × 388.30
  4. Step 4: Simplify right side
    668.02x = 357,910.92
  5. Step 5: Solve for x
    x = 357,910.92/668.02
  6. Step 6: Final answer
    x = 535.78

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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.