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Finding the Fourth Proportional to 86.36, 129.42 and 52.20

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Solution

The fourth proportional to 86.36, 129.42 and 52.20 is: 78.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.36 : 129.42 = 52.20 : x
  2. Step 2: Convert to fraction form
    86.36/129.42 = 52.20/x
  3. Step 3: Cross multiply
    86.36x = 129.42 × 52.20
  4. Step 4: Simplify right side
    86.36x = 6,755.72
  5. Step 5: Solve for x
    x = 6,755.72/86.36
  6. Step 6: Final answer
    x = 78.23

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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.