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Finding the Fourth Proportional to 137.55, 205.20 and 121.50

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Solution

The fourth proportional to 137.55, 205.20 and 121.50 is: 181.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.55 : 205.20 = 121.50 : x
  2. Step 2: Convert to fraction form
    137.55/205.20 = 121.50/x
  3. Step 3: Cross multiply
    137.55x = 205.20 × 121.50
  4. Step 4: Simplify right side
    137.55x = 24,931.80
  5. Step 5: Solve for x
    x = 24,931.80/137.55
  6. Step 6: Final answer
    x = 181.26

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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.