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Finding the Fourth Proportional to 489.74, 734.09 and 258.57

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Solution

The fourth proportional to 489.74, 734.09 and 258.57 is: 387.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.74 : 734.09 = 258.57 : x
  2. Step 2: Convert to fraction form
    489.74/734.09 = 258.57/x
  3. Step 3: Cross multiply
    489.74x = 734.09 × 258.57
  4. Step 4: Simplify right side
    489.74x = 189,812.36
  5. Step 5: Solve for x
    x = 189,812.36/489.74
  6. Step 6: Final answer
    x = 387.58

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.