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Finding the Fourth Proportional to 123.18, 185.20 and 99.30

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Solution

The fourth proportional to 123.18, 185.20 and 99.30 is: 149.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    123.18 : 185.20 = 99.30 : x
  2. Step 2: Convert to fraction form
    123.18/185.20 = 99.30/x
  3. Step 3: Cross multiply
    123.18x = 185.20 × 99.30
  4. Step 4: Simplify right side
    123.18x = 18,390.36
  5. Step 5: Solve for x
    x = 18,390.36/123.18
  6. Step 6: Final answer
    x = 149.30

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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.