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Finding the Fourth Proportional to 398.18, 549.49 and 221.14

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Solution

The fourth proportional to 398.18, 549.49 and 221.14 is: 305.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.18 : 549.49 = 221.14 : x
  2. Step 2: Convert to fraction form
    398.18/549.49 = 221.14/x
  3. Step 3: Cross multiply
    398.18x = 549.49 × 221.14
  4. Step 4: Simplify right side
    398.18x = 121,512.29
  5. Step 5: Solve for x
    x = 121,512.29/398.18
  6. Step 6: Final answer
    x = 305.17

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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.