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Finding the Fourth Proportional to 421.90, 633.04 and 205.62

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Solution

The fourth proportional to 421.90, 633.04 and 205.62 is: 308.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.90 : 633.04 = 205.62 : x
  2. Step 2: Convert to fraction form
    421.90/633.04 = 205.62/x
  3. Step 3: Cross multiply
    421.90x = 633.04 × 205.62
  4. Step 4: Simplify right side
    421.90x = 130,165.68
  5. Step 5: Solve for x
    x = 130,165.68/421.90
  6. Step 6: Final answer
    x = 308.52

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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.