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Finding the Fourth Proportional to 518.83, 777.71 and 387.91

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Solution

The fourth proportional to 518.83, 777.71 and 387.91 is: 581.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.83 : 777.71 = 387.91 : x
  2. Step 2: Convert to fraction form
    518.83/777.71 = 387.91/x
  3. Step 3: Cross multiply
    518.83x = 777.71 × 387.91
  4. Step 4: Simplify right side
    518.83x = 301,681.49
  5. Step 5: Solve for x
    x = 301,681.49/518.83
  6. Step 6: Final answer
    x = 581.47

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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.