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Finding the Fourth Proportional to 285.05, 427.78 and 220.21

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Solution

The fourth proportional to 285.05, 427.78 and 220.21 is: 330.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.05 : 427.78 = 220.21 : x
  2. Step 2: Convert to fraction form
    285.05/427.78 = 220.21/x
  3. Step 3: Cross multiply
    285.05x = 427.78 × 220.21
  4. Step 4: Simplify right side
    285.05x = 94,202.24
  5. Step 5: Solve for x
    x = 94,202.24/285.05
  6. Step 6: Final answer
    x = 330.48

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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.