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Finding the Fourth Proportional to 139.18, 208.76 and 70.70

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Solution

The fourth proportional to 139.18, 208.76 and 70.70 is: 106.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.18 : 208.76 = 70.70 : x
  2. Step 2: Convert to fraction form
    139.18/208.76 = 70.70/x
  3. Step 3: Cross multiply
    139.18x = 208.76 × 70.70
  4. Step 4: Simplify right side
    139.18x = 14,758.23
  5. Step 5: Solve for x
    x = 14,758.23/139.18
  6. Step 6: Final answer
    x = 106.04

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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.