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Finding the Fourth Proportional to 68.65, 102.80 and 57.16

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Solution

The fourth proportional to 68.65, 102.80 and 57.16 is: 85.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.65 : 102.80 = 57.16 : x
  2. Step 2: Convert to fraction form
    68.65/102.80 = 57.16/x
  3. Step 3: Cross multiply
    68.65x = 102.80 × 57.16
  4. Step 4: Simplify right side
    68.65x = 5,876.05
  5. Step 5: Solve for x
    x = 5,876.05/68.65
  6. Step 6: Final answer
    x = 85.59

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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.