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Finding the Fourth Proportional to 139.70, 210.38 and 131.60

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Solution

The fourth proportional to 139.70, 210.38 and 131.60 is: 198.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.70 : 210.38 = 131.60 : x
  2. Step 2: Convert to fraction form
    139.70/210.38 = 131.60/x
  3. Step 3: Cross multiply
    139.70x = 210.38 × 131.60
  4. Step 4: Simplify right side
    139.70x = 27,686.01
  5. Step 5: Solve for x
    x = 27,686.01/139.70
  6. Step 6: Final answer
    x = 198.18

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.