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Finding the Fourth Proportional to 656.39, 906.39 and 490.31

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Solution

The fourth proportional to 656.39, 906.39 and 490.31 is: 677.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.39 : 906.39 = 490.31 : x
  2. Step 2: Convert to fraction form
    656.39/906.39 = 490.31/x
  3. Step 3: Cross multiply
    656.39x = 906.39 × 490.31
  4. Step 4: Simplify right side
    656.39x = 444,407.55
  5. Step 5: Solve for x
    x = 444,407.55/656.39
  6. Step 6: Final answer
    x = 677.05

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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.