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Finding the Fourth Proportional to 88.28, 121.56 and 76.61

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Solution

The fourth proportional to 88.28, 121.56 and 76.61 is: 105.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.28 : 121.56 = 76.61 : x
  2. Step 2: Convert to fraction form
    88.28/121.56 = 76.61/x
  3. Step 3: Cross multiply
    88.28x = 121.56 × 76.61
  4. Step 4: Simplify right side
    88.28x = 9,312.71
  5. Step 5: Solve for x
    x = 9,312.71/88.28
  6. Step 6: Final answer
    x = 105.49

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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.