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Finding the Fourth Proportional to 839.84, 1,259.78 and 406.71

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Solution

The fourth proportional to 839.84, 1,259.78 and 406.71 is: 610.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    839.84 : 1,259.78 = 406.71 : x
  2. Step 2: Convert to fraction form
    839.84/1,259.78 = 406.71/x
  3. Step 3: Cross multiply
    839.84x = 1,259.78 × 406.71
  4. Step 4: Simplify right side
    839.84x = 512,363.09
  5. Step 5: Solve for x
    x = 512,363.09/839.84
  6. Step 6: Final answer
    x = 610.08

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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.