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Finding the Fourth Proportional to 210.60, 315.91 and 129.30

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Solution

The fourth proportional to 210.60, 315.91 and 129.30 is: 193.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.60 : 315.91 = 129.30 : x
  2. Step 2: Convert to fraction form
    210.60/315.91 = 129.30/x
  3. Step 3: Cross multiply
    210.60x = 315.91 × 129.30
  4. Step 4: Simplify right side
    210.60x = 40,846.84
  5. Step 5: Solve for x
    x = 40,846.84/210.60
  6. Step 6: Final answer
    x = 193.95

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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.