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Finding the Fourth Proportional to 328.14, 489.66 and 258.90

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Solution

The fourth proportional to 328.14, 489.66 and 258.90 is: 386.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    328.14 : 489.66 = 258.90 : x
  2. Step 2: Convert to fraction form
    328.14/489.66 = 258.90/x
  3. Step 3: Cross multiply
    328.14x = 489.66 × 258.90
  4. Step 4: Simplify right side
    328.14x = 126,772.97
  5. Step 5: Solve for x
    x = 126,772.97/328.14
  6. Step 6: Final answer
    x = 386.34

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.