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Finding the Fourth Proportional to 640.91, 959.30 and 455.69

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Solution

The fourth proportional to 640.91, 959.30 and 455.69 is: 682.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.91 : 959.30 = 455.69 : x
  2. Step 2: Convert to fraction form
    640.91/959.30 = 455.69/x
  3. Step 3: Cross multiply
    640.91x = 959.30 × 455.69
  4. Step 4: Simplify right side
    640.91x = 437,146.95
  5. Step 5: Solve for x
    x = 437,146.95/640.91
  6. Step 6: Final answer
    x = 682.08

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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.