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Finding the Fourth Proportional to 256.89, 383.78 and 205.66

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Solution

The fourth proportional to 256.89, 383.78 and 205.66 is: 307.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.89 : 383.78 = 205.66 : x
  2. Step 2: Convert to fraction form
    256.89/383.78 = 205.66/x
  3. Step 3: Cross multiply
    256.89x = 383.78 × 205.66
  4. Step 4: Simplify right side
    256.89x = 78,928.19
  5. Step 5: Solve for x
    x = 78,928.19/256.89
  6. Step 6: Final answer
    x = 307.25

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.