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Finding the Fourth Proportional to 256.40, 353.84 and 139.96

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Solution

The fourth proportional to 256.40, 353.84 and 139.96 is: 193.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.40 : 353.84 = 139.96 : x
  2. Step 2: Convert to fraction form
    256.40/353.84 = 139.96/x
  3. Step 3: Cross multiply
    256.40x = 353.84 × 139.96
  4. Step 4: Simplify right side
    256.40x = 49,523.45
  5. Step 5: Solve for x
    x = 49,523.45/256.40
  6. Step 6: Final answer
    x = 193.15

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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.