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Finding the Fourth Proportional to 4.20, 5.79 and 4

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Solution

The fourth proportional to 4.20, 5.79 and 4 is: 5.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    4.20 : 5.79 = 4 : x
  2. Step 2: Convert to fraction form
    4.20/5.79 = 4/x
  3. Step 3: Cross multiply
    4.20x = 5.79 × 4
  4. Step 4: Simplify right side
    4.20x = 23.16
  5. Step 5: Solve for x
    x = 23.16/4.20
  6. Step 6: Final answer
    x = 5.51

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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.