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Finding the Fourth Proportional to 321.08, 443.95 and 280.07

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Solution

The fourth proportional to 321.08, 443.95 and 280.07 is: 387.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.08 : 443.95 = 280.07 : x
  2. Step 2: Convert to fraction form
    321.08/443.95 = 280.07/x
  3. Step 3: Cross multiply
    321.08x = 443.95 × 280.07
  4. Step 4: Simplify right side
    321.08x = 124,335.82
  5. Step 5: Solve for x
    x = 124,335.82/321.08
  6. Step 6: Final answer
    x = 387.25

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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.