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Finding the Fourth Proportional to 639.17, 881.21 and 417.74

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Solution

The fourth proportional to 639.17, 881.21 and 417.74 is: 575.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.17 : 881.21 = 417.74 : x
  2. Step 2: Convert to fraction form
    639.17/881.21 = 417.74/x
  3. Step 3: Cross multiply
    639.17x = 881.21 × 417.74
  4. Step 4: Simplify right side
    639.17x = 368,114.58
  5. Step 5: Solve for x
    x = 368,114.58/639.17
  6. Step 6: Final answer
    x = 575.93

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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.