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Finding the Fourth Proportional to 520, 779.39 and 288.78

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Solution

The fourth proportional to 520, 779.39 and 288.78 is: 432.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    520 : 779.39 = 288.78 : x
  2. Step 2: Convert to fraction form
    520/779.39 = 288.78/x
  3. Step 3: Cross multiply
    520x = 779.39 × 288.78
  4. Step 4: Simplify right side
    520x = 225,072.97
  5. Step 5: Solve for x
    x = 225,072.97/520
  6. Step 6: Final answer
    x = 432.83

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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.