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Finding the Fourth Proportional to 421.81, 633.93 and 205.54

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Solution

The fourth proportional to 421.81, 633.93 and 205.54 is: 308.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.81 : 633.93 = 205.54 : x
  2. Step 2: Convert to fraction form
    421.81/633.93 = 205.54/x
  3. Step 3: Cross multiply
    421.81x = 633.93 × 205.54
  4. Step 4: Simplify right side
    421.81x = 130,297.97
  5. Step 5: Solve for x
    x = 130,297.97/421.81
  6. Step 6: Final answer
    x = 308.90

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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.