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Finding the Fourth Proportional to 421.90, 633.13 and 205.63

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Solution

The fourth proportional to 421.90, 633.13 and 205.63 is: 308.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.90 : 633.13 = 205.63 : x
  2. Step 2: Convert to fraction form
    421.90/633.13 = 205.63/x
  3. Step 3: Cross multiply
    421.90x = 633.13 × 205.63
  4. Step 4: Simplify right side
    421.90x = 130,190.52
  5. Step 5: Solve for x
    x = 130,190.52/421.90
  6. Step 6: Final answer
    x = 308.58

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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.