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Finding the Fourth Proportional to 806.45, 1,209.83 and 286.49

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Solution

The fourth proportional to 806.45, 1,209.83 and 286.49 is: 429.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.45 : 1,209.83 = 286.49 : x
  2. Step 2: Convert to fraction form
    806.45/1,209.83 = 286.49/x
  3. Step 3: Cross multiply
    806.45x = 1,209.83 × 286.49
  4. Step 4: Simplify right side
    806.45x = 346,596.72
  5. Step 5: Solve for x
    x = 346,596.72/806.45
  6. Step 6: Final answer
    x = 429.78

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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.