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Finding the Fourth Proportional to 49.80, 68.74 and 38.90

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Solution

The fourth proportional to 49.80, 68.74 and 38.90 is: 53.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    49.80 : 68.74 = 38.90 : x
  2. Step 2: Convert to fraction form
    49.80/68.74 = 38.90/x
  3. Step 3: Cross multiply
    49.80x = 68.74 × 38.90
  4. Step 4: Simplify right side
    49.80x = 2,673.99
  5. Step 5: Solve for x
    x = 2,673.99/49.80
  6. Step 6: Final answer
    x = 53.69

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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.