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Finding the Fourth Proportional to 656.86, 906.42 and 394.78

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Solution

The fourth proportional to 656.86, 906.42 and 394.78 is: 544.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.86 : 906.42 = 394.78 : x
  2. Step 2: Convert to fraction form
    656.86/906.42 = 394.78/x
  3. Step 3: Cross multiply
    656.86x = 906.42 × 394.78
  4. Step 4: Simplify right side
    656.86x = 357,836.49
  5. Step 5: Solve for x
    x = 357,836.49/656.86
  6. Step 6: Final answer
    x = 544.77

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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.