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Finding the Fourth Proportional to 68.09, 102.15 and 20

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Solution

The fourth proportional to 68.09, 102.15 and 20 is: 30.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.09 : 102.15 = 20 : x
  2. Step 2: Convert to fraction form
    68.09/102.15 = 20/x
  3. Step 3: Cross multiply
    68.09x = 102.15 × 20
  4. Step 4: Simplify right side
    68.09x = 2,043
  5. Step 5: Solve for x
    x = 2,043/68.09
  6. Step 6: Final answer
    x = 30.00

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.