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Finding the Fourth Proportional to 421.71, 581.80 and 255.86

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Solution

The fourth proportional to 421.71, 581.80 and 255.86 is: 352.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.71 : 581.80 = 255.86 : x
  2. Step 2: Convert to fraction form
    421.71/581.80 = 255.86/x
  3. Step 3: Cross multiply
    421.71x = 581.80 × 255.86
  4. Step 4: Simplify right side
    421.71x = 148,859.35
  5. Step 5: Solve for x
    x = 148,859.35/421.71
  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.