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Finding the Fourth Proportional to 86.09, 118.85 and 53.39

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Solution

The fourth proportional to 86.09, 118.85 and 53.39 is: 73.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.09 : 118.85 = 53.39 : x
  2. Step 2: Convert to fraction form
    86.09/118.85 = 53.39/x
  3. Step 3: Cross multiply
    86.09x = 118.85 × 53.39
  4. Step 4: Simplify right side
    86.09x = 6,345.43
  5. Step 5: Solve for x
    x = 6,345.43/86.09
  6. Step 6: Final answer
    x = 73.71

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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.