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Finding the Fourth Proportional to 640.63, 960.94 and 256.15

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Solution

The fourth proportional to 640.63, 960.94 and 256.15 is: 384.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.63 : 960.94 = 256.15 : x
  2. Step 2: Convert to fraction form
    640.63/960.94 = 256.15/x
  3. Step 3: Cross multiply
    640.63x = 960.94 × 256.15
  4. Step 4: Simplify right side
    640.63x = 246,144.78
  5. Step 5: Solve for x
    x = 246,144.78/640.63
  6. Step 6: Final answer
    x = 384.22

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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.