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Finding the Fourth Proportional to 210.56, 315.38 and 129.15

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Solution

The fourth proportional to 210.56, 315.38 and 129.15 is: 193.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.56 : 315.38 = 129.15 : x
  2. Step 2: Convert to fraction form
    210.56/315.38 = 129.15/x
  3. Step 3: Cross multiply
    210.56x = 315.38 × 129.15
  4. Step 4: Simplify right side
    210.56x = 40,730.68
  5. Step 5: Solve for x
    x = 40,730.68/210.56
  6. Step 6: Final answer
    x = 193.44

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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.