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Finding the Fourth Proportional to 310.61, 428.70 and 205.71

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Solution

The fourth proportional to 310.61, 428.70 and 205.71 is: 283.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.61 : 428.70 = 205.71 : x
  2. Step 2: Convert to fraction form
    310.61/428.70 = 205.71/x
  3. Step 3: Cross multiply
    310.61x = 428.70 × 205.71
  4. Step 4: Simplify right side
    310.61x = 88,187.88
  5. Step 5: Solve for x
    x = 88,187.88/310.61
  6. Step 6: Final answer
    x = 283.92

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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.