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Finding the Fourth Proportional to 68.65, 102.86 and 66.15

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Solution

The fourth proportional to 68.65, 102.86 and 66.15 is: 99.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.65 : 102.86 = 66.15 : x
  2. Step 2: Convert to fraction form
    68.65/102.86 = 66.15/x
  3. Step 3: Cross multiply
    68.65x = 102.86 × 66.15
  4. Step 4: Simplify right side
    68.65x = 6,804.19
  5. Step 5: Solve for x
    x = 6,804.19/68.65
  6. Step 6: Final answer
    x = 99.11

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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.