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Finding the Fourth Proportional to 630.79, 945.11 and 386.80

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Solution

The fourth proportional to 630.79, 945.11 and 386.80 is: 579.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.79 : 945.11 = 386.80 : x
  2. Step 2: Convert to fraction form
    630.79/945.11 = 386.80/x
  3. Step 3: Cross multiply
    630.79x = 945.11 × 386.80
  4. Step 4: Simplify right side
    630.79x = 365,568.55
  5. Step 5: Solve for x
    x = 365,568.55/630.79
  6. Step 6: Final answer
    x = 579.54

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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.