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Finding the Fourth Proportional to 429.04, 639.47 and 405.40

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Solution

The fourth proportional to 429.04, 639.47 and 405.40 is: 604.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.04 : 639.47 = 405.40 : x
  2. Step 2: Convert to fraction form
    429.04/639.47 = 405.40/x
  3. Step 3: Cross multiply
    429.04x = 639.47 × 405.40
  4. Step 4: Simplify right side
    429.04x = 259,241.14
  5. Step 5: Solve for x
    x = 259,241.14/429.04
  6. Step 6: Final answer
    x = 604.24

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.