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Finding the Fourth Proportional to 288.75, 398.49 and 218.68

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Solution

The fourth proportional to 288.75, 398.49 and 218.68 is: 301.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.75 : 398.49 = 218.68 : x
  2. Step 2: Convert to fraction form
    288.75/398.49 = 218.68/x
  3. Step 3: Cross multiply
    288.75x = 398.49 × 218.68
  4. Step 4: Simplify right side
    288.75x = 87,141.79
  5. Step 5: Solve for x
    x = 87,141.79/288.75
  6. Step 6: Final answer
    x = 301.79

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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.