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Finding the Fourth Proportional to 126.20, 189.30 and 99.47

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Solution

The fourth proportional to 126.20, 189.30 and 99.47 is: 149.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    126.20 : 189.30 = 99.47 : x
  2. Step 2: Convert to fraction form
    126.20/189.30 = 99.47/x
  3. Step 3: Cross multiply
    126.20x = 189.30 × 99.47
  4. Step 4: Simplify right side
    126.20x = 18,828.72
  5. Step 5: Solve for x
    x = 18,828.72/126.20
  6. Step 6: Final answer
    x = 149.20

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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.