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Finding the Fourth Proportional to 210.85, 315.72 and 137.61

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Solution

The fourth proportional to 210.85, 315.72 and 137.61 is: 206.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.85 : 315.72 = 137.61 : x
  2. Step 2: Convert to fraction form
    210.85/315.72 = 137.61/x
  3. Step 3: Cross multiply
    210.85x = 315.72 × 137.61
  4. Step 4: Simplify right side
    210.85x = 43,446.23
  5. Step 5: Solve for x
    x = 43,446.23/210.85
  6. Step 6: Final answer
    x = 206.06

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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.