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Finding the Fourth Proportional to 640.63, 883.72 and 428.30

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Solution

The fourth proportional to 640.63, 883.72 and 428.30 is: 590.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.63 : 883.72 = 428.30 : x
  2. Step 2: Convert to fraction form
    640.63/883.72 = 428.30/x
  3. Step 3: Cross multiply
    640.63x = 883.72 × 428.30
  4. Step 4: Simplify right side
    640.63x = 378,498.41
  5. Step 5: Solve for x
    x = 378,498.41/640.63
  6. Step 6: Final answer
    x = 590.82

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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.