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Finding the Fourth Proportional to 216.81, 325.02 and 139.80

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Solution

The fourth proportional to 216.81, 325.02 and 139.80 is: 209.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    216.81 : 325.02 = 139.80 : x
  2. Step 2: Convert to fraction form
    216.81/325.02 = 139.80/x
  3. Step 3: Cross multiply
    216.81x = 325.02 × 139.80
  4. Step 4: Simplify right side
    216.81x = 45,437.80
  5. Step 5: Solve for x
    x = 45,437.80/216.81
  6. Step 6: Final answer
    x = 209.57

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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.