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Finding the Fourth Proportional to 68.64, 102.88 and 64.64

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Solution

The fourth proportional to 68.64, 102.88 and 64.64 is: 96.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.64 : 102.88 = 64.64 : x
  2. Step 2: Convert to fraction form
    68.64/102.88 = 64.64/x
  3. Step 3: Cross multiply
    68.64x = 102.88 × 64.64
  4. Step 4: Simplify right side
    68.64x = 6,650.16
  5. Step 5: Solve for x
    x = 6,650.16/68.64
  6. Step 6: Final answer
    x = 96.88

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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.