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Finding the Fourth Proportional to 421.66, 581.78 and 255.84

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Solution

The fourth proportional to 421.66, 581.78 and 255.84 is: 352.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.66 : 581.78 = 255.84 : x
  2. Step 2: Convert to fraction form
    421.66/581.78 = 255.84/x
  3. Step 3: Cross multiply
    421.66x = 581.78 × 255.84
  4. Step 4: Simplify right side
    421.66x = 148,842.60
  5. Step 5: Solve for x
    x = 148,842.60/421.66
  6. Step 6: Final answer
    x = 352.99

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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.