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Finding the Fourth Proportional to 398.08, 549.26 and 287.72

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Solution

The fourth proportional to 398.08, 549.26 and 287.72 is: 396.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.08 : 549.26 = 287.72 : x
  2. Step 2: Convert to fraction form
    398.08/549.26 = 287.72/x
  3. Step 3: Cross multiply
    398.08x = 549.26 × 287.72
  4. Step 4: Simplify right side
    398.08x = 158,033.09
  5. Step 5: Solve for x
    x = 158,033.09/398.08
  6. Step 6: Final answer
    x = 396.99

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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.