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Finding the Fourth Proportional to 668.21, 921.69 and 406.35

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Solution

The fourth proportional to 668.21, 921.69 and 406.35 is: 560.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.21 : 921.69 = 406.35 : x
  2. Step 2: Convert to fraction form
    668.21/921.69 = 406.35/x
  3. Step 3: Cross multiply
    668.21x = 921.69 × 406.35
  4. Step 4: Simplify right side
    668.21x = 374,528.73
  5. Step 5: Solve for x
    x = 374,528.73/668.21
  6. Step 6: Final answer
    x = 560.50

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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.