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Finding the Fourth Proportional to 397.91, 549.18 and 287.75

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Solution

The fourth proportional to 397.91, 549.18 and 287.75 is: 397.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    397.91 : 549.18 = 287.75 : x
  2. Step 2: Convert to fraction form
    397.91/549.18 = 287.75/x
  3. Step 3: Cross multiply
    397.91x = 549.18 × 287.75
  4. Step 4: Simplify right side
    397.91x = 158,027.92
  5. Step 5: Solve for x
    x = 158,027.92/397.91
  6. Step 6: Final answer
    x = 397.14

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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.