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Finding the Fourth Proportional to 68.30, 102.38 and 53.15

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Solution

The fourth proportional to 68.30, 102.38 and 53.15 is: 79.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.30 : 102.38 = 53.15 : x
  2. Step 2: Convert to fraction form
    68.30/102.38 = 53.15/x
  3. Step 3: Cross multiply
    68.30x = 102.38 × 53.15
  4. Step 4: Simplify right side
    68.30x = 5,440.72
  5. Step 5: Solve for x
    x = 5,440.72/68.30
  6. Step 6: Final answer
    x = 79.66

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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.