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Finding the Fourth Proportional to 781.00, 1,077.19 and 511.65

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Solution

The fourth proportional to 781.00, 1,077.19 and 511.65 is: 705.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    781.00 : 1,077.19 = 511.65 : x
  2. Step 2: Convert to fraction form
    781.00/1,077.19 = 511.65/x
  3. Step 3: Cross multiply
    781.00x = 1,077.19 × 511.65
  4. Step 4: Simplify right side
    781.00x = 551,142.98
  5. Step 5: Solve for x
    x = 551,142.98/781.00
  6. Step 6: Final answer
    x = 705.69

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.