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Finding the Fourth Proportional to 310.32, 428.56 and 309.71

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Solution

The fourth proportional to 310.32, 428.56 and 309.71 is: 427.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.32 : 428.56 = 309.71 : x
  2. Step 2: Convert to fraction form
    310.32/428.56 = 309.71/x
  3. Step 3: Cross multiply
    310.32x = 428.56 × 309.71
  4. Step 4: Simplify right side
    310.32x = 132,729.61
  5. Step 5: Solve for x
    x = 132,729.61/310.32
  6. Step 6: Final answer
    x = 427.72

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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.