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Finding the Fourth Proportional to 630.78, 945.22 and 386.90

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Solution

The fourth proportional to 630.78, 945.22 and 386.90 is: 579.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.78 : 945.22 = 386.90 : x
  2. Step 2: Convert to fraction form
    630.78/945.22 = 386.90/x
  3. Step 3: Cross multiply
    630.78x = 945.22 × 386.90
  4. Step 4: Simplify right side
    630.78x = 365,705.62
  5. Step 5: Solve for x
    x = 365,705.62/630.78
  6. Step 6: Final answer
    x = 579.77

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.