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Finding the Fourth Proportional to 89.30, 133.21 and 87.23

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Solution

The fourth proportional to 89.30, 133.21 and 87.23 is: 130.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    89.30 : 133.21 = 87.23 : x
  2. Step 2: Convert to fraction form
    89.30/133.21 = 87.23/x
  3. Step 3: Cross multiply
    89.30x = 133.21 × 87.23
  4. Step 4: Simplify right side
    89.30x = 11,619.91
  5. Step 5: Solve for x
    x = 11,619.91/89.30
  6. Step 6: Final answer
    x = 130.12

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.