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Finding the Fourth Proportional to 3.79, 5.20 and 3.57

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Solution

The fourth proportional to 3.79, 5.20 and 3.57 is: 4.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.79 : 5.20 = 3.57 : x
  2. Step 2: Convert to fraction form
    3.79/5.20 = 3.57/x
  3. Step 3: Cross multiply
    3.79x = 5.20 × 3.57
  4. Step 4: Simplify right side
    3.79x = 18.54
  5. Step 5: Solve for x
    x = 18.54/3.79
  6. Step 6: Final answer
    x = 4.90

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.