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Finding the Fourth Proportional to 2.12, 3.20 and 1.99

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Solution

The fourth proportional to 2.12, 3.20 and 1.99 is: 3.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.12 : 3.20 = 1.99 : x
  2. Step 2: Convert to fraction form
    2.12/3.20 = 1.99/x
  3. Step 3: Cross multiply
    2.12x = 3.20 × 1.99
  4. Step 4: Simplify right side
    2.12x = 6.37
  5. Step 5: Solve for x
    x = 6.37/2.12
  6. Step 6: Final answer
    x = 3.00

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.