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Finding the Fourth Proportional to 520.88, 717.78 and 389.66

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Solution

The fourth proportional to 520.88, 717.78 and 389.66 is: 536.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.88 : 717.78 = 389.66 : x
  2. Step 2: Convert to fraction form
    520.88/717.78 = 389.66/x
  3. Step 3: Cross multiply
    520.88x = 717.78 × 389.66
  4. Step 4: Simplify right side
    520.88x = 279,690.15
  5. Step 5: Solve for x
    x = 279,690.15/520.88
  6. Step 6: Final answer
    x = 536.96

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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.