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Finding the Fourth Proportional to 310.38, 428.28 and 248.40

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Solution

The fourth proportional to 310.38, 428.28 and 248.40 is: 342.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.38 : 428.28 = 248.40 : x
  2. Step 2: Convert to fraction form
    310.38/428.28 = 248.40/x
  3. Step 3: Cross multiply
    310.38x = 428.28 × 248.40
  4. Step 4: Simplify right side
    310.38x = 106,384.75
  5. Step 5: Solve for x
    x = 106,384.75/310.38
  6. Step 6: Final answer
    x = 342.76

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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.