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Finding the Fourth Proportional to 256.98, 385.23 and 126.90

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Solution

The fourth proportional to 256.98, 385.23 and 126.90 is: 190.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.98 : 385.23 = 126.90 : x
  2. Step 2: Convert to fraction form
    256.98/385.23 = 126.90/x
  3. Step 3: Cross multiply
    256.98x = 385.23 × 126.90
  4. Step 4: Simplify right side
    256.98x = 48,885.69
  5. Step 5: Solve for x
    x = 48,885.69/256.98
  6. Step 6: Final answer
    x = 190.23

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.