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Finding the Fourth Proportional to 668.09, 921.76 and 388.27

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Solution

The fourth proportional to 668.09, 921.76 and 388.27 is: 535.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.09 : 921.76 = 388.27 : x
  2. Step 2: Convert to fraction form
    668.09/921.76 = 388.27/x
  3. Step 3: Cross multiply
    668.09x = 921.76 × 388.27
  4. Step 4: Simplify right side
    668.09x = 357,885.21
  5. Step 5: Solve for x
    x = 357,885.21/668.09
  6. Step 6: Final answer
    x = 535.69

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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.