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Finding the Fourth Proportional to 87.23, 120.13 and 71.63

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Solution

The fourth proportional to 87.23, 120.13 and 71.63 is: 98.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.23 : 120.13 = 71.63 : x
  2. Step 2: Convert to fraction form
    87.23/120.13 = 71.63/x
  3. Step 3: Cross multiply
    87.23x = 120.13 × 71.63
  4. Step 4: Simplify right side
    87.23x = 8,605.66
  5. Step 5: Solve for x
    x = 8,605.66/87.23
  6. Step 6: Final answer
    x = 98.66

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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.