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Finding the Fourth Proportional to 216.42, 324.10 and 139.15

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Solution

The fourth proportional to 216.42, 324.10 and 139.15 is: 208.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    216.42 : 324.10 = 139.15 : x
  2. Step 2: Convert to fraction form
    216.42/324.10 = 139.15/x
  3. Step 3: Cross multiply
    216.42x = 324.10 × 139.15
  4. Step 4: Simplify right side
    216.42x = 45,098.52
  5. Step 5: Solve for x
    x = 45,098.52/216.42
  6. Step 6: Final answer
    x = 208.38

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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.