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Finding the Fourth Proportional to 256.71, 354.33 and 221.58

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Solution

The fourth proportional to 256.71, 354.33 and 221.58 is: 305.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.71 : 354.33 = 221.58 : x
  2. Step 2: Convert to fraction form
    256.71/354.33 = 221.58/x
  3. Step 3: Cross multiply
    256.71x = 354.33 × 221.58
  4. Step 4: Simplify right side
    256.71x = 78,512.44
  5. Step 5: Solve for x
    x = 78,512.44/256.71
  6. Step 6: Final answer
    x = 305.84

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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.