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Finding the Fourth Proportional to 308.88, 427.95 and 287.82

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Solution

The fourth proportional to 308.88, 427.95 and 287.82 is: 398.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    308.88 : 427.95 = 287.82 : x
  2. Step 2: Convert to fraction form
    308.88/427.95 = 287.82/x
  3. Step 3: Cross multiply
    308.88x = 427.95 × 287.82
  4. Step 4: Simplify right side
    308.88x = 123,172.57
  5. Step 5: Solve for x
    x = 123,172.57/308.88
  6. Step 6: Final answer
    x = 398.77

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.