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Finding the Fourth Proportional to 428.92, 640.26 and 371.52

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Solution

The fourth proportional to 428.92, 640.26 and 371.52 is: 554.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.92 : 640.26 = 371.52 : x
  2. Step 2: Convert to fraction form
    428.92/640.26 = 371.52/x
  3. Step 3: Cross multiply
    428.92x = 640.26 × 371.52
  4. Step 4: Simplify right side
    428.92x = 237,869.40
  5. Step 5: Solve for x
    x = 237,869.40/428.92
  6. Step 6: Final answer
    x = 554.58

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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.