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Finding the Fourth Proportional to 487.30, 672.36 and 321.79

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Solution

The fourth proportional to 487.30, 672.36 and 321.79 is: 443.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.30 : 672.36 = 321.79 : x
  2. Step 2: Convert to fraction form
    487.30/672.36 = 321.79/x
  3. Step 3: Cross multiply
    487.30x = 672.36 × 321.79
  4. Step 4: Simplify right side
    487.30x = 216,358.72
  5. Step 5: Solve for x
    x = 216,358.72/487.30
  6. Step 6: Final answer
    x = 443.99

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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.