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Finding the Fourth Proportional to 88.28, 131.72 and 86.22

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Solution

The fourth proportional to 88.28, 131.72 and 86.22 is: 128.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.28 : 131.72 = 86.22 : x
  2. Step 2: Convert to fraction form
    88.28/131.72 = 86.22/x
  3. Step 3: Cross multiply
    88.28x = 131.72 × 86.22
  4. Step 4: Simplify right side
    88.28x = 11,356.47
  5. Step 5: Solve for x
    x = 11,356.47/88.28
  6. Step 6: Final answer
    x = 128.64

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.