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Finding the Fourth Proportional to 310.55, 428.45 and 199.82

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Solution

The fourth proportional to 310.55, 428.45 and 199.82 is: 275.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.55 : 428.45 = 199.82 : x
  2. Step 2: Convert to fraction form
    310.55/428.45 = 199.82/x
  3. Step 3: Cross multiply
    310.55x = 428.45 × 199.82
  4. Step 4: Simplify right side
    310.55x = 85,609.74
  5. Step 5: Solve for x
    x = 85,609.74/310.55
  6. Step 6: Final answer
    x = 275.68

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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.