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Finding the Fourth Proportional to 447.21, 670.86 and 139.08

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Solution

The fourth proportional to 447.21, 670.86 and 139.08 is: 208.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    447.21 : 670.86 = 139.08 : x
  2. Step 2: Convert to fraction form
    447.21/670.86 = 139.08/x
  3. Step 3: Cross multiply
    447.21x = 670.86 × 139.08
  4. Step 4: Simplify right side
    447.21x = 93,303.21
  5. Step 5: Solve for x
    x = 93,303.21/447.21
  6. Step 6: Final answer
    x = 208.63

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.