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Finding the Fourth Proportional to 90.70, 125.49 and 79.23

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Solution

The fourth proportional to 90.70, 125.49 and 79.23 is: 109.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.70 : 125.49 = 79.23 : x
  2. Step 2: Convert to fraction form
    90.70/125.49 = 79.23/x
  3. Step 3: Cross multiply
    90.70x = 125.49 × 79.23
  4. Step 4: Simplify right side
    90.70x = 9,942.57
  5. Step 5: Solve for x
    x = 9,942.57/90.70
  6. Step 6: Final answer
    x = 109.62

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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.