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Finding the Fourth Proportional to 321.09, 442.90 and 203.10

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Solution

The fourth proportional to 321.09, 442.90 and 203.10 is: 280.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.09 : 442.90 = 203.10 : x
  2. Step 2: Convert to fraction form
    321.09/442.90 = 203.10/x
  3. Step 3: Cross multiply
    321.09x = 442.90 × 203.10
  4. Step 4: Simplify right side
    321.09x = 89,952.99
  5. Step 5: Solve for x
    x = 89,952.99/321.09
  6. Step 6: Final answer
    x = 280.15

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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.