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Finding the Fourth Proportional to 121.21, 181.88 and 98.65

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Solution

The fourth proportional to 121.21, 181.88 and 98.65 is: 148.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.21 : 181.88 = 98.65 : x
  2. Step 2: Convert to fraction form
    121.21/181.88 = 98.65/x
  3. Step 3: Cross multiply
    121.21x = 181.88 × 98.65
  4. Step 4: Simplify right side
    121.21x = 17,942.46
  5. Step 5: Solve for x
    x = 17,942.46/121.21
  6. Step 6: Final answer
    x = 148.03

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.