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Finding the Fourth Proportional to 271.80, 407.68 and 76.80

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Solution

The fourth proportional to 271.80, 407.68 and 76.80 is: 115.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    271.80 : 407.68 = 76.80 : x
  2. Step 2: Convert to fraction form
    271.80/407.68 = 76.80/x
  3. Step 3: Cross multiply
    271.80x = 407.68 × 76.80
  4. Step 4: Simplify right side
    271.80x = 31,311.45
  5. Step 5: Solve for x
    x = 31,311.45/271.80
  6. Step 6: Final answer
    x = 115.20

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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.