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Finding the Fourth Proportional to 421.32, 581.39 and 234.78

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Solution

The fourth proportional to 421.32, 581.39 and 234.78 is: 323.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.32 : 581.39 = 234.78 : x
  2. Step 2: Convert to fraction form
    421.32/581.39 = 234.78/x
  3. Step 3: Cross multiply
    421.32x = 581.39 × 234.78
  4. Step 4: Simplify right side
    421.32x = 136,497.57
  5. Step 5: Solve for x
    x = 136,497.57/421.32
  6. Step 6: Final answer
    x = 323.98

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.