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Finding the Fourth Proportional to 305.82, 422.07 and 279.90

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Solution

The fourth proportional to 305.82, 422.07 and 279.90 is: 386.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.82 : 422.07 = 279.90 : x
  2. Step 2: Convert to fraction form
    305.82/422.07 = 279.90/x
  3. Step 3: Cross multiply
    305.82x = 422.07 × 279.90
  4. Step 4: Simplify right side
    305.82x = 118,137.39
  5. Step 5: Solve for x
    x = 118,137.39/305.82
  6. Step 6: Final answer
    x = 386.30

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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.