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Finding the Fourth Proportional to 429.54, 639.08 and 428.46

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Solution

The fourth proportional to 429.54, 639.08 and 428.46 is: 637.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.54 : 639.08 = 428.46 : x
  2. Step 2: Convert to fraction form
    429.54/639.08 = 428.46/x
  3. Step 3: Cross multiply
    429.54x = 639.08 × 428.46
  4. Step 4: Simplify right side
    429.54x = 273,818.07
  5. Step 5: Solve for x
    x = 273,818.07/429.54
  6. Step 6: Final answer
    x = 637.47

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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.