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Finding the Fourth Proportional to 489.80, 734.52 and 215.75

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Solution

The fourth proportional to 489.80, 734.52 and 215.75 is: 323.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.80 : 734.52 = 215.75 : x
  2. Step 2: Convert to fraction form
    489.80/734.52 = 215.75/x
  3. Step 3: Cross multiply
    489.80x = 734.52 × 215.75
  4. Step 4: Simplify right side
    489.80x = 158,472.69
  5. Step 5: Solve for x
    x = 158,472.69/489.80
  6. Step 6: Final answer
    x = 323.55

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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.