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Finding the Fourth Proportional to 87.07, 120.15 and 66.36

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Solution

The fourth proportional to 87.07, 120.15 and 66.36 is: 91.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.07 : 120.15 = 66.36 : x
  2. Step 2: Convert to fraction form
    87.07/120.15 = 66.36/x
  3. Step 3: Cross multiply
    87.07x = 120.15 × 66.36
  4. Step 4: Simplify right side
    87.07x = 7,972.22
  5. Step 5: Solve for x
    x = 7,972.22/87.07
  6. Step 6: Final answer
    x = 91.57

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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.