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Finding the Fourth Proportional to 571.30, 788.39 and 309.31

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Solution

The fourth proportional to 571.30, 788.39 and 309.31 is: 426.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    571.30 : 788.39 = 309.31 : x
  2. Step 2: Convert to fraction form
    571.30/788.39 = 309.31/x
  3. Step 3: Cross multiply
    571.30x = 788.39 × 309.31
  4. Step 4: Simplify right side
    571.30x = 243,858.99
  5. Step 5: Solve for x
    x = 243,858.99/571.30
  6. Step 6: Final answer
    x = 426.85

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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.