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Finding the Fourth Proportional to 630.80, 870.56 and 351.09

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Solution

The fourth proportional to 630.80, 870.56 and 351.09 is: 484.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.80 : 870.56 = 351.09 : x
  2. Step 2: Convert to fraction form
    630.80/870.56 = 351.09/x
  3. Step 3: Cross multiply
    630.80x = 870.56 × 351.09
  4. Step 4: Simplify right side
    630.80x = 305,644.91
  5. Step 5: Solve for x
    x = 305,644.91/630.80
  6. Step 6: Final answer
    x = 484.54

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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.