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Finding the Fourth Proportional to 86.34, 129.75 and 52.12

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Solution

The fourth proportional to 86.34, 129.75 and 52.12 is: 78.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.34 : 129.75 = 52.12 : x
  2. Step 2: Convert to fraction form
    86.34/129.75 = 52.12/x
  3. Step 3: Cross multiply
    86.34x = 129.75 × 52.12
  4. Step 4: Simplify right side
    86.34x = 6,762.57
  5. Step 5: Solve for x
    x = 6,762.57/86.34
  6. Step 6: Final answer
    x = 78.32

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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.