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Finding the Fourth Proportional to 653.91, 980.91 and 221.10

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Solution

The fourth proportional to 653.91, 980.91 and 221.10 is: 331.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.91 : 980.91 = 221.10 : x
  2. Step 2: Convert to fraction form
    653.91/980.91 = 221.10/x
  3. Step 3: Cross multiply
    653.91x = 980.91 × 221.10
  4. Step 4: Simplify right side
    653.91x = 216,879.20
  5. Step 5: Solve for x
    x = 216,879.20/653.91
  6. Step 6: Final answer
    x = 331.67

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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.