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Finding the Fourth Proportional to 398.05, 549.12 and 258.21

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Solution

The fourth proportional to 398.05, 549.12 and 258.21 is: 356.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.05 : 549.12 = 258.21 : x
  2. Step 2: Convert to fraction form
    398.05/549.12 = 258.21/x
  3. Step 3: Cross multiply
    398.05x = 549.12 × 258.21
  4. Step 4: Simplify right side
    398.05x = 141,789.24
  5. Step 5: Solve for x
    x = 141,789.24/398.05
  6. Step 6: Final answer
    x = 356.21

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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.