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Finding the Fourth Proportional to 298.40, 411.64 and 209.84

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Solution

The fourth proportional to 298.40, 411.64 and 209.84 is: 289.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    298.40 : 411.64 = 209.84 : x
  2. Step 2: Convert to fraction form
    298.40/411.64 = 209.84/x
  3. Step 3: Cross multiply
    298.40x = 411.64 × 209.84
  4. Step 4: Simplify right side
    298.40x = 86,378.54
  5. Step 5: Solve for x
    x = 86,378.54/298.40
  6. Step 6: Final answer
    x = 289.47

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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.