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Finding the Fourth Proportional to 68.36, 102.31 and 56.21

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Solution

The fourth proportional to 68.36, 102.31 and 56.21 is: 84.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.36 : 102.31 = 56.21 : x
  2. Step 2: Convert to fraction form
    68.36/102.31 = 56.21/x
  3. Step 3: Cross multiply
    68.36x = 102.31 × 56.21
  4. Step 4: Simplify right side
    68.36x = 5,751.08
  5. Step 5: Solve for x
    x = 5,751.08/68.36
  6. Step 6: Final answer
    x = 84.13

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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.