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Finding the Fourth Proportional to 427.45, 640.58 and 221.59

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Solution

The fourth proportional to 427.45, 640.58 and 221.59 is: 332.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.45 : 640.58 = 221.59 : x
  2. Step 2: Convert to fraction form
    427.45/640.58 = 221.59/x
  3. Step 3: Cross multiply
    427.45x = 640.58 × 221.59
  4. Step 4: Simplify right side
    427.45x = 141,949.49
  5. Step 5: Solve for x
    x = 141,949.49/427.45
  6. Step 6: Final answer
    x = 332.08

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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.