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Finding the Fourth Proportional to 639.63, 883.22 and 418.77

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Solution

The fourth proportional to 639.63, 883.22 and 418.77 is: 578.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.63 : 883.22 = 418.77 : x
  2. Step 2: Convert to fraction form
    639.63/883.22 = 418.77/x
  3. Step 3: Cross multiply
    639.63x = 883.22 × 418.77
  4. Step 4: Simplify right side
    639.63x = 369,863.95
  5. Step 5: Solve for x
    x = 369,863.95/639.63
  6. Step 6: Final answer
    x = 578.25

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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.