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Finding the Fourth Proportional to 636.68, 879.02 and 489.02

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Solution

The fourth proportional to 636.68, 879.02 and 489.02 is: 675.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    636.68 : 879.02 = 489.02 : x
  2. Step 2: Convert to fraction form
    636.68/879.02 = 489.02/x
  3. Step 3: Cross multiply
    636.68x = 879.02 × 489.02
  4. Step 4: Simplify right side
    636.68x = 429,855.92
  5. Step 5: Solve for x
    x = 429,855.92/636.68
  6. Step 6: Final answer
    x = 675.15

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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.