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Finding the Fourth Proportional to 571.20, 788.25 and 309.21

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Solution

The fourth proportional to 571.20, 788.25 and 309.21 is: 426.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    571.20 : 788.25 = 309.21 : x
  2. Step 2: Convert to fraction form
    571.20/788.25 = 309.21/x
  3. Step 3: Cross multiply
    571.20x = 788.25 × 309.21
  4. Step 4: Simplify right side
    571.20x = 243,733.24
  5. Step 5: Solve for x
    x = 243,733.24/571.20
  6. Step 6: Final answer
    x = 426.71

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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.