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Finding the Fourth Proportional to 126.89, 190.29 and 72.80

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Solution

The fourth proportional to 126.89, 190.29 and 72.80 is: 109.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    126.89 : 190.29 = 72.80 : x
  2. Step 2: Convert to fraction form
    126.89/190.29 = 72.80/x
  3. Step 3: Cross multiply
    126.89x = 190.29 × 72.80
  4. Step 4: Simplify right side
    126.89x = 13,853.11
  5. Step 5: Solve for x
    x = 13,853.11/126.89
  6. Step 6: Final answer
    x = 109.17

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.