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Finding the Fourth Proportional to 256.90, 385.80 and 199.18

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Solution

The fourth proportional to 256.90, 385.80 and 199.18 is: 299.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.90 : 385.80 = 199.18 : x
  2. Step 2: Convert to fraction form
    256.90/385.80 = 199.18/x
  3. Step 3: Cross multiply
    256.90x = 385.80 × 199.18
  4. Step 4: Simplify right side
    256.90x = 76,845.30
  5. Step 5: Solve for x
    x = 76,845.30/256.90
  6. Step 6: Final answer
    x = 299.13

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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.