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Finding the Fourth Proportional to 201.80, 302.70 and 120.80

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Solution

The fourth proportional to 201.80, 302.70 and 120.80 is: 181.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    201.80 : 302.70 = 120.80 : x
  2. Step 2: Convert to fraction form
    201.80/302.70 = 120.80/x
  3. Step 3: Cross multiply
    201.80x = 302.70 × 120.80
  4. Step 4: Simplify right side
    201.80x = 36,566.16
  5. Step 5: Solve for x
    x = 36,566.16/201.80
  6. Step 6: Final answer
    x = 181.20

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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.