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Finding the Fourth Proportional to 398.30, 549.70 and 223.70

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Solution

The fourth proportional to 398.30, 549.70 and 223.70 is: 308.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.30 : 549.70 = 223.70 : x
  2. Step 2: Convert to fraction form
    398.30/549.70 = 223.70/x
  3. Step 3: Cross multiply
    398.30x = 549.70 × 223.70
  4. Step 4: Simplify right side
    398.30x = 122,967.89
  5. Step 5: Solve for x
    x = 122,967.89/398.30
  6. Step 6: Final answer
    x = 308.73

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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.