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Finding the Fourth Proportional to 103.17, 142.29 and 77.25

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Solution

The fourth proportional to 103.17, 142.29 and 77.25 is: 106.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.17 : 142.29 = 77.25 : x
  2. Step 2: Convert to fraction form
    103.17/142.29 = 77.25/x
  3. Step 3: Cross multiply
    103.17x = 142.29 × 77.25
  4. Step 4: Simplify right side
    103.17x = 10,991.90
  5. Step 5: Solve for x
    x = 10,991.90/103.17
  6. Step 6: Final answer
    x = 106.54

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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.