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Finding the Fourth Proportional to 68.85, 103.68 and 64.80

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Solution

The fourth proportional to 68.85, 103.68 and 64.80 is: 97.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    68.85 : 103.68 = 64.80 : x
  2. Step 2: Convert to fraction form
    68.85/103.68 = 64.80/x
  3. Step 3: Cross multiply
    68.85x = 103.68 × 64.80
  4. Step 4: Simplify right side
    68.85x = 6,718.46
  5. Step 5: Solve for x
    x = 6,718.46/68.85
  6. Step 6: Final answer
    x = 97.58

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.