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Finding the Fourth Proportional to 805.83, 1,208.57 and 278.71

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Solution

The fourth proportional to 805.83, 1,208.57 and 278.71 is: 418.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.83 : 1,208.57 = 278.71 : x
  2. Step 2: Convert to fraction form
    805.83/1,208.57 = 278.71/x
  3. Step 3: Cross multiply
    805.83x = 1,208.57 × 278.71
  4. Step 4: Simplify right side
    805.83x = 336,840.54
  5. Step 5: Solve for x
    x = 336,840.54/805.83
  6. Step 6: Final answer
    x = 418.00

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.