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Finding the Fourth Proportional to 149.40, 206.16 and 90.39

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Solution

The fourth proportional to 149.40, 206.16 and 90.39 is: 124.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    149.40 : 206.16 = 90.39 : x
  2. Step 2: Convert to fraction form
    149.40/206.16 = 90.39/x
  3. Step 3: Cross multiply
    149.40x = 206.16 × 90.39
  4. Step 4: Simplify right side
    149.40x = 18,634.80
  5. Step 5: Solve for x
    x = 18,634.80/149.40
  6. Step 6: Final answer
    x = 124.73

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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.