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Finding the Fourth Proportional to 310.25, 428.15 and 172.25

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Solution

The fourth proportional to 310.25, 428.15 and 172.25 is: 237.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.25 : 428.15 = 172.25 : x
  2. Step 2: Convert to fraction form
    310.25/428.15 = 172.25/x
  3. Step 3: Cross multiply
    310.25x = 428.15 × 172.25
  4. Step 4: Simplify right side
    310.25x = 73,747.98
  5. Step 5: Solve for x
    x = 73,747.98/310.25
  6. Step 6: Final answer
    x = 237.71

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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.