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Finding the Fourth Proportional to 130.28, 195.40 and 81.51

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Solution

The fourth proportional to 130.28, 195.40 and 81.51 is: 122.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.28 : 195.40 = 81.51 : x
  2. Step 2: Convert to fraction form
    130.28/195.40 = 81.51/x
  3. Step 3: Cross multiply
    130.28x = 195.40 × 81.51
  4. Step 4: Simplify right side
    130.28x = 15,926.85
  5. Step 5: Solve for x
    x = 15,926.85/130.28
  6. Step 6: Final answer
    x = 122.25

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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.