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Finding the Fourth Proportional to 639.25, 881.85 and 556.22

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Solution

The fourth proportional to 639.25, 881.85 and 556.22 is: 767.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.25 : 881.85 = 556.22 : x
  2. Step 2: Convert to fraction form
    639.25/881.85 = 556.22/x
  3. Step 3: Cross multiply
    639.25x = 881.85 × 556.22
  4. Step 4: Simplify right side
    639.25x = 490,506.90
  5. Step 5: Solve for x
    x = 490,506.90/639.25
  6. Step 6: Final answer
    x = 767.32

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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.