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Finding the Fourth Proportional to 438.21, 604.12 and 290.79

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Solution

The fourth proportional to 438.21, 604.12 and 290.79 is: 400.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.21 : 604.12 = 290.79 : x
  2. Step 2: Convert to fraction form
    438.21/604.12 = 290.79/x
  3. Step 3: Cross multiply
    438.21x = 604.12 × 290.79
  4. Step 4: Simplify right side
    438.21x = 175,671.33
  5. Step 5: Solve for x
    x = 175,671.33/438.21
  6. Step 6: Final answer
    x = 400.88

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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.