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Finding the Fourth Proportional to 656.91, 906.85 and 408.40

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Solution

The fourth proportional to 656.91, 906.85 and 408.40 is: 563.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.91 : 906.85 = 408.40 : x
  2. Step 2: Convert to fraction form
    656.91/906.85 = 408.40/x
  3. Step 3: Cross multiply
    656.91x = 906.85 × 408.40
  4. Step 4: Simplify right side
    656.91x = 370,357.54
  5. Step 5: Solve for x
    x = 370,357.54/656.91
  6. Step 6: Final answer
    x = 563.79

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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.