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Finding the Fourth Proportional to 489.12, 673.78 and 418.95

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Solution

The fourth proportional to 489.12, 673.78 and 418.95 is: 577.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.12 : 673.78 = 418.95 : x
  2. Step 2: Convert to fraction form
    489.12/673.78 = 418.95/x
  3. Step 3: Cross multiply
    489.12x = 673.78 × 418.95
  4. Step 4: Simplify right side
    489.12x = 282,280.13
  5. Step 5: Solve for x
    x = 282,280.13/489.12
  6. Step 6: Final answer
    x = 577.12

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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.