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Finding the Fourth Proportional to 626.70, 864.84 and 393.78

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Solution

The fourth proportional to 626.70, 864.84 and 393.78 is: 543.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    626.70 : 864.84 = 393.78 : x
  2. Step 2: Convert to fraction form
    626.70/864.84 = 393.78/x
  3. Step 3: Cross multiply
    626.70x = 864.84 × 393.78
  4. Step 4: Simplify right side
    626.70x = 340,556.70
  5. Step 5: Solve for x
    x = 340,556.70/626.70
  6. Step 6: Final answer
    x = 543.41

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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.