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Finding the Fourth Proportional to 640.76, 961.50 and 256.04

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Solution

The fourth proportional to 640.76, 961.50 and 256.04 is: 384.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.76 : 961.50 = 256.04 : x
  2. Step 2: Convert to fraction form
    640.76/961.50 = 256.04/x
  3. Step 3: Cross multiply
    640.76x = 961.50 × 256.04
  4. Step 4: Simplify right side
    640.76x = 246,182.46
  5. Step 5: Solve for x
    x = 246,182.46/640.76
  6. Step 6: Final answer
    x = 384.20

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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.