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Finding the Fourth Proportional to 639.39, 964.40 and 563.31

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Solution

The fourth proportional to 639.39, 964.40 and 563.31 is: 849.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.39 : 964.40 = 563.31 : x
  2. Step 2: Convert to fraction form
    639.39/964.40 = 563.31/x
  3. Step 3: Cross multiply
    639.39x = 964.40 × 563.31
  4. Step 4: Simplify right side
    639.39x = 543,256.16
  5. Step 5: Solve for x
    x = 543,256.16/639.39
  6. Step 6: Final answer
    x = 849.65

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.