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Finding the Fourth Proportional to 298.68, 409.84 and 287.76

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Solution

The fourth proportional to 298.68, 409.84 and 287.76 is: 394.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    298.68 : 409.84 = 287.76 : x
  2. Step 2: Convert to fraction form
    298.68/409.84 = 287.76/x
  3. Step 3: Cross multiply
    298.68x = 409.84 × 287.76
  4. Step 4: Simplify right side
    298.68x = 117,935.56
  5. Step 5: Solve for x
    x = 117,935.56/298.68
  6. Step 6: Final answer
    x = 394.86

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.