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Finding the Fourth Proportional to 806.25, 1,209.47 and 459.39

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Solution

The fourth proportional to 806.25, 1,209.47 and 459.39 is: 689.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.25 : 1,209.47 = 459.39 : x
  2. Step 2: Convert to fraction form
    806.25/1,209.47 = 459.39/x
  3. Step 3: Cross multiply
    806.25x = 1,209.47 × 459.39
  4. Step 4: Simplify right side
    806.25x = 555,616.13
  5. Step 5: Solve for x
    x = 555,616.13/806.25
  6. Step 6: Final answer
    x = 689.14

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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.