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Finding the Fourth Proportional to 421.82, 631.56 and 215.94

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Solution

The fourth proportional to 421.82, 631.56 and 215.94 is: 323.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.82 : 631.56 = 215.94 : x
  2. Step 2: Convert to fraction form
    421.82/631.56 = 215.94/x
  3. Step 3: Cross multiply
    421.82x = 631.56 × 215.94
  4. Step 4: Simplify right side
    421.82x = 136,379.07
  5. Step 5: Solve for x
    x = 136,379.07/421.82
  6. Step 6: Final answer
    x = 323.31

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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.