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Finding the Fourth Proportional to 256.71, 383.81 and 218.64

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Solution

The fourth proportional to 256.71, 383.81 and 218.64 is: 326.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.71 : 383.81 = 218.64 : x
  2. Step 2: Convert to fraction form
    256.71/383.81 = 218.64/x
  3. Step 3: Cross multiply
    256.71x = 383.81 × 218.64
  4. Step 4: Simplify right side
    256.71x = 83,916.22
  5. Step 5: Solve for x
    x = 83,916.22/256.71
  6. Step 6: Final answer
    x = 326.89

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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.