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Finding the Fourth Proportional to 806.86, 1,210.76 and 319.85

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Solution

The fourth proportional to 806.86, 1,210.76 and 319.85 is: 479.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.86 : 1,210.76 = 319.85 : x
  2. Step 2: Convert to fraction form
    806.86/1,210.76 = 319.85/x
  3. Step 3: Cross multiply
    806.86x = 1,210.76 × 319.85
  4. Step 4: Simplify right side
    806.86x = 387,253.93
  5. Step 5: Solve for x
    x = 387,253.93/806.86
  6. Step 6: Final answer
    x = 479.95

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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.