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Finding the Fourth Proportional to 138.48, 208.68 and 114.63

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Solution

The fourth proportional to 138.48, 208.68 and 114.63 is: 172.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.48 : 208.68 = 114.63 : x
  2. Step 2: Convert to fraction form
    138.48/208.68 = 114.63/x
  3. Step 3: Cross multiply
    138.48x = 208.68 × 114.63
  4. Step 4: Simplify right side
    138.48x = 23,920.95
  5. Step 5: Solve for x
    x = 23,920.95/138.48
  6. Step 6: Final answer
    x = 172.74

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.