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Finding the Fourth Proportional to 427.84, 640.32 and 256

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Solution

The fourth proportional to 427.84, 640.32 and 256 is: 383.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.84 : 640.32 = 256 : x
  2. Step 2: Convert to fraction form
    427.84/640.32 = 256/x
  3. Step 3: Cross multiply
    427.84x = 640.32 × 256
  4. Step 4: Simplify right side
    427.84x = 163,921.92
  5. Step 5: Solve for x
    x = 163,921.92/427.84
  6. Step 6: Final answer
    x = 383.14

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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.