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Finding the Fourth Proportional to 654.21, 980.71 and 221.06

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Solution

The fourth proportional to 654.21, 980.71 and 221.06 is: 331.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.21 : 980.71 = 221.06 : x
  2. Step 2: Convert to fraction form
    654.21/980.71 = 221.06/x
  3. Step 3: Cross multiply
    654.21x = 980.71 × 221.06
  4. Step 4: Simplify right side
    654.21x = 216,797.65
  5. Step 5: Solve for x
    x = 216,797.65/654.21
  6. Step 6: Final answer
    x = 331.39

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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.