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Finding the Fourth Proportional to 640.98, 961.47 and 256.23

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Solution

The fourth proportional to 640.98, 961.47 and 256.23 is: 384.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.98 : 961.47 = 256.23 : x
  2. Step 2: Convert to fraction form
    640.98/961.47 = 256.23/x
  3. Step 3: Cross multiply
    640.98x = 961.47 × 256.23
  4. Step 4: Simplify right side
    640.98x = 246,357.46
  5. Step 5: Solve for x
    x = 246,357.46/640.98
  6. Step 6: Final answer
    x = 384.35

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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.