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Finding the Fourth Proportional to 625.79, 863.75 and 389.88

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Solution

The fourth proportional to 625.79, 863.75 and 389.88 is: 538.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    625.79 : 863.75 = 389.88 : x
  2. Step 2: Convert to fraction form
    625.79/863.75 = 389.88/x
  3. Step 3: Cross multiply
    625.79x = 863.75 × 389.88
  4. Step 4: Simplify right side
    625.79x = 336,758.85
  5. Step 5: Solve for x
    x = 336,758.85/625.79
  6. Step 6: Final answer
    x = 538.13

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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.