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Finding the Fourth Proportional to 438.78, 605.79 and 305.96

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Solution

The fourth proportional to 438.78, 605.79 and 305.96 is: 422.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.78 : 605.79 = 305.96 : x
  2. Step 2: Convert to fraction form
    438.78/605.79 = 305.96/x
  3. Step 3: Cross multiply
    438.78x = 605.79 × 305.96
  4. Step 4: Simplify right side
    438.78x = 185,347.51
  5. Step 5: Solve for x
    x = 185,347.51/438.78
  6. Step 6: Final answer
    x = 422.42

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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.