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Finding the Fourth Proportional to 427.54, 640.62 and 221.80

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Solution

The fourth proportional to 427.54, 640.62 and 221.80 is: 332.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.54 : 640.62 = 221.80 : x
  2. Step 2: Convert to fraction form
    427.54/640.62 = 221.80/x
  3. Step 3: Cross multiply
    427.54x = 640.62 × 221.80
  4. Step 4: Simplify right side
    427.54x = 142,089.52
  5. Step 5: Solve for x
    x = 142,089.52/427.54
  6. Step 6: Final answer
    x = 332.34

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.