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Finding the Fourth Proportional to 121.02, 180.66 and 108.78

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Solution

The fourth proportional to 121.02, 180.66 and 108.78 is: 162.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.02 : 180.66 = 108.78 : x
  2. Step 2: Convert to fraction form
    121.02/180.66 = 108.78/x
  3. Step 3: Cross multiply
    121.02x = 180.66 × 108.78
  4. Step 4: Simplify right side
    121.02x = 19,652.19
  5. Step 5: Solve for x
    x = 19,652.19/121.02
  6. Step 6: Final answer
    x = 162.39

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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.