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Finding the Fourth Proportional to 219.72, 329.58 and 89.78

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Solution

The fourth proportional to 219.72, 329.58 and 89.78 is: 134.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    219.72 : 329.58 = 89.78 : x
  2. Step 2: Convert to fraction form
    219.72/329.58 = 89.78/x
  3. Step 3: Cross multiply
    219.72x = 329.58 × 89.78
  4. Step 4: Simplify right side
    219.72x = 29,590.52
  5. Step 5: Solve for x
    x = 29,590.52/219.72
  6. Step 6: Final answer
    x = 134.67

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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.