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Finding the Fourth Proportional to 637.05, 879.21 and 489.63

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Solution

The fourth proportional to 637.05, 879.21 and 489.63 is: 675.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    637.05 : 879.21 = 489.63 : x
  2. Step 2: Convert to fraction form
    637.05/879.21 = 489.63/x
  3. Step 3: Cross multiply
    637.05x = 879.21 × 489.63
  4. Step 4: Simplify right side
    637.05x = 430,487.59
  5. Step 5: Solve for x
    x = 430,487.59/637.05
  6. Step 6: Final answer
    x = 675.75

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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.