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Finding the Fourth Proportional to 519.86, 718.26 and 389.72

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Solution

The fourth proportional to 519.86, 718.26 and 389.72 is: 538.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    519.86 : 718.26 = 389.72 : x
  2. Step 2: Convert to fraction form
    519.86/718.26 = 389.72/x
  3. Step 3: Cross multiply
    519.86x = 718.26 × 389.72
  4. Step 4: Simplify right side
    519.86x = 279,920.29
  5. Step 5: Solve for x
    x = 279,920.29/519.86
  6. Step 6: Final answer
    x = 538.45

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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.