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Finding the Fourth Proportional to 628.70, 867.60 and 395.78

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Solution

The fourth proportional to 628.70, 867.60 and 395.78 is: 546.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.70 : 867.60 = 395.78 : x
  2. Step 2: Convert to fraction form
    628.70/867.60 = 395.78/x
  3. Step 3: Cross multiply
    628.70x = 867.60 × 395.78
  4. Step 4: Simplify right side
    628.70x = 343,378.73
  5. Step 5: Solve for x
    x = 343,378.73/628.70
  6. Step 6: Final answer
    x = 546.17

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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.