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Finding the Fourth Proportional to 239.31, 330.19 and 139.71

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Solution

The fourth proportional to 239.31, 330.19 and 139.71 is: 192.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    239.31 : 330.19 = 139.71 : x
  2. Step 2: Convert to fraction form
    239.31/330.19 = 139.71/x
  3. Step 3: Cross multiply
    239.31x = 330.19 × 139.71
  4. Step 4: Simplify right side
    239.31x = 46,130.84
  5. Step 5: Solve for x
    x = 46,130.84/239.31
  6. Step 6: Final answer
    x = 192.77

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.