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Finding the Fourth Proportional to 640.97, 961.70 and 256.25

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Solution

The fourth proportional to 640.97, 961.70 and 256.25 is: 384.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.97 : 961.70 = 256.25 : x
  2. Step 2: Convert to fraction form
    640.97/961.70 = 256.25/x
  3. Step 3: Cross multiply
    640.97x = 961.70 × 256.25
  4. Step 4: Simplify right side
    640.97x = 246,434.34
  5. Step 5: Solve for x
    x = 246,434.34/640.97
  6. Step 6: Final answer
    x = 384.47

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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.