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Finding the Fourth Proportional to 640.88, 883.96 and 631.28

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Solution

The fourth proportional to 640.88, 883.96 and 631.28 is: 870.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.88 : 883.96 = 631.28 : x
  2. Step 2: Convert to fraction form
    640.88/883.96 = 631.28/x
  3. Step 3: Cross multiply
    640.88x = 883.96 × 631.28
  4. Step 4: Simplify right side
    640.88x = 558,026.27
  5. Step 5: Solve for x
    x = 558,026.27/640.88
  6. Step 6: Final answer
    x = 870.72

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.