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Finding the Fourth Proportional to 398.06, 549.21 and 242.78

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Solution

The fourth proportional to 398.06, 549.21 and 242.78 is: 334.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.06 : 549.21 = 242.78 : x
  2. Step 2: Convert to fraction form
    398.06/549.21 = 242.78/x
  3. Step 3: Cross multiply
    398.06x = 549.21 × 242.78
  4. Step 4: Simplify right side
    398.06x = 133,337.20
  5. Step 5: Solve for x
    x = 133,337.20/398.06
  6. Step 6: Final answer
    x = 334.97

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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.