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Finding the Fourth Proportional to 288.69, 398.69 and 218.63

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Solution

The fourth proportional to 288.69, 398.69 and 218.63 is: 301.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.69 : 398.69 = 218.63 : x
  2. Step 2: Convert to fraction form
    288.69/398.69 = 218.63/x
  3. Step 3: Cross multiply
    288.69x = 398.69 × 218.63
  4. Step 4: Simplify right side
    288.69x = 87,162.51
  5. Step 5: Solve for x
    x = 87,162.51/288.69
  6. Step 6: Final answer
    x = 301.92

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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.