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Finding the Fourth Proportional to 639.08, 955.61 and 455.91

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Solution

The fourth proportional to 639.08, 955.61 and 455.91 is: 681.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.08 : 955.61 = 455.91 : x
  2. Step 2: Convert to fraction form
    639.08/955.61 = 455.91/x
  3. Step 3: Cross multiply
    639.08x = 955.61 × 455.91
  4. Step 4: Simplify right side
    639.08x = 435,672.16
  5. Step 5: Solve for x
    x = 435,672.16/639.08
  6. Step 6: Final answer
    x = 681.72

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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.