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Finding the Fourth Proportional to 806.39, 1,209.62 and 286.47

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Solution

The fourth proportional to 806.39, 1,209.62 and 286.47 is: 429.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.39 : 1,209.62 = 286.47 : x
  2. Step 2: Convert to fraction form
    806.39/1,209.62 = 286.47/x
  3. Step 3: Cross multiply
    806.39x = 1,209.62 × 286.47
  4. Step 4: Simplify right side
    806.39x = 346,519.84
  5. Step 5: Solve for x
    x = 346,519.84/806.39
  6. Step 6: Final answer
    x = 429.72

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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.