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Finding the Fourth Proportional to 139.24, 208.84 and 100.79

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Solution

The fourth proportional to 139.24, 208.84 and 100.79 is: 151.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.24 : 208.84 = 100.79 : x
  2. Step 2: Convert to fraction form
    139.24/208.84 = 100.79/x
  3. Step 3: Cross multiply
    139.24x = 208.84 × 100.79
  4. Step 4: Simplify right side
    139.24x = 21,048.98
  5. Step 5: Solve for x
    x = 21,048.98/139.24
  6. Step 6: Final answer
    x = 151.17

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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.