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Finding the Fourth Proportional to 638.98, 880.86 and 489.67

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Solution

The fourth proportional to 638.98, 880.86 and 489.67 is: 675.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.98 : 880.86 = 489.67 : x
  2. Step 2: Convert to fraction form
    638.98/880.86 = 489.67/x
  3. Step 3: Cross multiply
    638.98x = 880.86 × 489.67
  4. Step 4: Simplify right side
    638.98x = 431,330.72
  5. Step 5: Solve for x
    x = 431,330.72/638.98
  6. Step 6: Final answer
    x = 675.03

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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.