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Finding the Fourth Proportional to 630.51, 869.85 and 397.50

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Solution

The fourth proportional to 630.51, 869.85 and 397.50 is: 548.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.51 : 869.85 = 397.50 : x
  2. Step 2: Convert to fraction form
    630.51/869.85 = 397.50/x
  3. Step 3: Cross multiply
    630.51x = 869.85 × 397.50
  4. Step 4: Simplify right side
    630.51x = 345,765.38
  5. Step 5: Solve for x
    x = 345,765.38/630.51
  6. Step 6: Final answer
    x = 548.39

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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.