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Finding the Fourth Proportional to 628.90, 867.86 and 349.12

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Solution

The fourth proportional to 628.90, 867.86 and 349.12 is: 481.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.90 : 867.86 = 349.12 : x
  2. Step 2: Convert to fraction form
    628.90/867.86 = 349.12/x
  3. Step 3: Cross multiply
    628.90x = 867.86 × 349.12
  4. Step 4: Simplify right side
    628.90x = 302,992.34
  5. Step 5: Solve for x
    x = 302,992.34/628.90
  6. Step 6: Final answer
    x = 481.78

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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.