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Finding the Fourth Proportional to 639.07, 881.93 and 355.51

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Solution

The fourth proportional to 639.07, 881.93 and 355.51 is: 490.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.07 : 881.93 = 355.51 : x
  2. Step 2: Convert to fraction form
    639.07/881.93 = 355.51/x
  3. Step 3: Cross multiply
    639.07x = 881.93 × 355.51
  4. Step 4: Simplify right side
    639.07x = 313,535.33
  5. Step 5: Solve for x
    x = 313,535.33/639.07
  6. Step 6: Final answer
    x = 490.61

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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.