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Finding the Fourth Proportional to 780.28, 1,077.27 and 518.38

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Solution

The fourth proportional to 780.28, 1,077.27 and 518.38 is: 715.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.28 : 1,077.27 = 518.38 : x
  2. Step 2: Convert to fraction form
    780.28/1,077.27 = 518.38/x
  3. Step 3: Cross multiply
    780.28x = 1,077.27 × 518.38
  4. Step 4: Simplify right side
    780.28x = 558,435.22
  5. Step 5: Solve for x
    x = 558,435.22/780.28
  6. Step 6: Final answer
    x = 715.69

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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.