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Finding the Fourth Proportional to 839.02, 1,256.64 and 513.70

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Solution

The fourth proportional to 839.02, 1,256.64 and 513.70 is: 769.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    839.02 : 1,256.64 = 513.70 : x
  2. Step 2: Convert to fraction form
    839.02/1,256.64 = 513.70/x
  3. Step 3: Cross multiply
    839.02x = 1,256.64 × 513.70
  4. Step 4: Simplify right side
    839.02x = 645,535.97
  5. Step 5: Solve for x
    x = 645,535.97/839.02
  6. Step 6: Final answer
    x = 769.39

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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.