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Finding the Fourth Proportional to 256.98, 385.71 and 135.30

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Solution

The fourth proportional to 256.98, 385.71 and 135.30 is: 203.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.98 : 385.71 = 135.30 : x
  2. Step 2: Convert to fraction form
    256.98/385.71 = 135.30/x
  3. Step 3: Cross multiply
    256.98x = 385.71 × 135.30
  4. Step 4: Simplify right side
    256.98x = 52,186.56
  5. Step 5: Solve for x
    x = 52,186.56/256.98
  6. Step 6: Final answer
    x = 203.08

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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.