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Finding the Fourth Proportional to 421.58, 581.79 and 255.75

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Solution

The fourth proportional to 421.58, 581.79 and 255.75 is: 352.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.58 : 581.79 = 255.75 : x
  2. Step 2: Convert to fraction form
    421.58/581.79 = 255.75/x
  3. Step 3: Cross multiply
    421.58x = 581.79 × 255.75
  4. Step 4: Simplify right side
    421.58x = 148,791.51
  5. Step 5: Solve for x
    x = 148,791.51/421.58
  6. Step 6: Final answer
    x = 352.94

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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.