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Finding the Fourth Proportional to 216.80, 325.08 and 79.86

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Solution

The fourth proportional to 216.80, 325.08 and 79.86 is: 119.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    216.80 : 325.08 = 79.86 : x
  2. Step 2: Convert to fraction form
    216.80/325.08 = 79.86/x
  3. Step 3: Cross multiply
    216.80x = 325.08 × 79.86
  4. Step 4: Simplify right side
    216.80x = 25,960.89
  5. Step 5: Solve for x
    x = 25,960.89/216.80
  6. Step 6: Final answer
    x = 119.75

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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.