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Finding the Fourth Proportional to 515.41, 777.60 and 489.79

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Solution

The fourth proportional to 515.41, 777.60 and 489.79 is: 738.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.41 : 777.60 = 489.79 : x
  2. Step 2: Convert to fraction form
    515.41/777.60 = 489.79/x
  3. Step 3: Cross multiply
    515.41x = 777.60 × 489.79
  4. Step 4: Simplify right side
    515.41x = 380,858.26
  5. Step 5: Solve for x
    x = 380,858.26/515.41
  6. Step 6: Final answer
    x = 738.95

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.