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Finding the Fourth Proportional to 330.94, 456.42 and 287.20

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Solution

The fourth proportional to 330.94, 456.42 and 287.20 is: 396.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    330.94 : 456.42 = 287.20 : x
  2. Step 2: Convert to fraction form
    330.94/456.42 = 287.20/x
  3. Step 3: Cross multiply
    330.94x = 456.42 × 287.20
  4. Step 4: Simplify right side
    330.94x = 131,083.82
  5. Step 5: Solve for x
    x = 131,083.82/330.94
  6. Step 6: Final answer
    x = 396.10

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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.