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Finding the Fourth Proportional to 398.59, 549.47 and 287.89

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Solution

The fourth proportional to 398.59, 549.47 and 287.89 is: 396.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.59 : 549.47 = 287.89 : x
  2. Step 2: Convert to fraction form
    398.59/549.47 = 287.89/x
  3. Step 3: Cross multiply
    398.59x = 549.47 × 287.89
  4. Step 4: Simplify right side
    398.59x = 158,186.26
  5. Step 5: Solve for x
    x = 158,186.26/398.59
  6. Step 6: Final answer
    x = 396.87

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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.