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Finding the Fourth Proportional to 256.09, 384.64 and 219.51

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Solution

The fourth proportional to 256.09, 384.64 and 219.51 is: 329.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.09 : 384.64 = 219.51 : x
  2. Step 2: Convert to fraction form
    256.09/384.64 = 219.51/x
  3. Step 3: Cross multiply
    256.09x = 384.64 × 219.51
  4. Step 4: Simplify right side
    256.09x = 84,432.33
  5. Step 5: Solve for x
    x = 84,432.33/256.09
  6. Step 6: Final answer
    x = 329.70

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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.