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Finding the Fourth Proportional to 487.14, 672.39 and 321.45

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Solution

The fourth proportional to 487.14, 672.39 and 321.45 is: 443.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.14 : 672.39 = 321.45 : x
  2. Step 2: Convert to fraction form
    487.14/672.39 = 321.45/x
  3. Step 3: Cross multiply
    487.14x = 672.39 × 321.45
  4. Step 4: Simplify right side
    487.14x = 216,139.77
  5. Step 5: Solve for x
    x = 216,139.77/487.14
  6. Step 6: Final answer
    x = 443.69

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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.