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Finding the Fourth Proportional to 90.10, 125.20 and 89.16

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Solution

The fourth proportional to 90.10, 125.20 and 89.16 is: 123.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.10 : 125.20 = 89.16 : x
  2. Step 2: Convert to fraction form
    90.10/125.20 = 89.16/x
  3. Step 3: Cross multiply
    90.10x = 125.20 × 89.16
  4. Step 4: Simplify right side
    90.10x = 11,162.83
  5. Step 5: Solve for x
    x = 11,162.83/90.10
  6. Step 6: Final answer
    x = 123.89

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.