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Finding the Fourth Proportional to 839.83, 1,260.08 and 429.07

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Solution

The fourth proportional to 839.83, 1,260.08 and 429.07 is: 643.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    839.83 : 1,260.08 = 429.07 : x
  2. Step 2: Convert to fraction form
    839.83/1,260.08 = 429.07/x
  3. Step 3: Cross multiply
    839.83x = 1,260.08 × 429.07
  4. Step 4: Simplify right side
    839.83x = 540,662.53
  5. Step 5: Solve for x
    x = 540,662.53/839.83
  6. Step 6: Final answer
    x = 643.78

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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.