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Finding the Fourth Proportional to 88.02, 121.28 and 69.57

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Solution

The fourth proportional to 88.02, 121.28 and 69.57 is: 95.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.02 : 121.28 = 69.57 : x
  2. Step 2: Convert to fraction form
    88.02/121.28 = 69.57/x
  3. Step 3: Cross multiply
    88.02x = 121.28 × 69.57
  4. Step 4: Simplify right side
    88.02x = 8,437.10
  5. Step 5: Solve for x
    x = 8,437.10/88.02
  6. Step 6: Final answer
    x = 95.85

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.