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Finding the Fourth Proportional to 806.20, 1,210.38 and 518.20

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Solution

The fourth proportional to 806.20, 1,210.38 and 518.20 is: 777.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.20 : 1,210.38 = 518.20 : x
  2. Step 2: Convert to fraction form
    806.20/1,210.38 = 518.20/x
  3. Step 3: Cross multiply
    806.20x = 1,210.38 × 518.20
  4. Step 4: Simplify right side
    806.20x = 627,218.92
  5. Step 5: Solve for x
    x = 627,218.92/806.20
  6. Step 6: Final answer
    x = 777.99

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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.