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Finding the Fourth Proportional to 115.20, 171.81 and 103.05

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Solution

The fourth proportional to 115.20, 171.81 and 103.05 is: 153.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    115.20 : 171.81 = 103.05 : x
  2. Step 2: Convert to fraction form
    115.20/171.81 = 103.05/x
  3. Step 3: Cross multiply
    115.20x = 171.81 × 103.05
  4. Step 4: Simplify right side
    115.20x = 17,705.02
  5. Step 5: Solve for x
    x = 17,705.02/115.20
  6. Step 6: Final answer
    x = 153.69

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.