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Finding the Fourth Proportional to 355.63, 490.77 and 208.21

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Solution

The fourth proportional to 355.63, 490.77 and 208.21 is: 287.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    355.63 : 490.77 = 208.21 : x
  2. Step 2: Convert to fraction form
    355.63/490.77 = 208.21/x
  3. Step 3: Cross multiply
    355.63x = 490.77 × 208.21
  4. Step 4: Simplify right side
    355.63x = 102,179.73
  5. Step 5: Solve for x
    x = 102,179.73/355.63
  6. Step 6: Final answer
    x = 287.32

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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.