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Finding the Fourth Proportional to 88.68, 121.80 and 78.96

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Solution

The fourth proportional to 88.68, 121.80 and 78.96 is: 108.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    88.68 : 121.80 = 78.96 : x
  2. Step 2: Convert to fraction form
    88.68/121.80 = 78.96/x
  3. Step 3: Cross multiply
    88.68x = 121.80 × 78.96
  4. Step 4: Simplify right side
    88.68x = 9,617.33
  5. Step 5: Solve for x
    x = 9,617.33/88.68
  6. Step 6: Final answer
    x = 108.45

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.