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Finding the Fourth Proportional to 87.30, 120.60 and 71.10

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Solution

The fourth proportional to 87.30, 120.60 and 71.10 is: 98.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.30 : 120.60 = 71.10 : x
  2. Step 2: Convert to fraction form
    87.30/120.60 = 71.10/x
  3. Step 3: Cross multiply
    87.30x = 120.60 × 71.10
  4. Step 4: Simplify right side
    87.30x = 8,574.66
  5. Step 5: Solve for x
    x = 8,574.66/87.30
  6. Step 6: Final answer
    x = 98.22

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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.