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Finding the Fourth Proportional to 806.30, 1,209.55 and 286.20

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Solution

The fourth proportional to 806.30, 1,209.55 and 286.20 is: 429.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.30 : 1,209.55 = 286.20 : x
  2. Step 2: Convert to fraction form
    806.30/1,209.55 = 286.20/x
  3. Step 3: Cross multiply
    806.30x = 1,209.55 × 286.20
  4. Step 4: Simplify right side
    806.30x = 346,173.21
  5. Step 5: Solve for x
    x = 346,173.21/806.30
  6. Step 6: Final answer
    x = 429.34

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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.