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Finding the Fourth Proportional to 428.92, 639.71 and 364.34

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Solution

The fourth proportional to 428.92, 639.71 and 364.34 is: 543.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.92 : 639.71 = 364.34 : x
  2. Step 2: Convert to fraction form
    428.92/639.71 = 364.34/x
  3. Step 3: Cross multiply
    428.92x = 639.71 × 364.34
  4. Step 4: Simplify right side
    428.92x = 233,071.94
  5. Step 5: Solve for x
    x = 233,071.94/428.92
  6. Step 6: Final answer
    x = 543.39

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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.