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Finding the Fourth Proportional to 421.82, 632.79 and 205.25

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Solution

The fourth proportional to 421.82, 632.79 and 205.25 is: 307.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.82 : 632.79 = 205.25 : x
  2. Step 2: Convert to fraction form
    421.82/632.79 = 205.25/x
  3. Step 3: Cross multiply
    421.82x = 632.79 × 205.25
  4. Step 4: Simplify right side
    421.82x = 129,880.15
  5. Step 5: Solve for x
    x = 129,880.15/421.82
  6. Step 6: Final answer
    x = 307.90

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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.