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Finding the Fourth Proportional to 131.78, 181.80 and 80

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Solution

The fourth proportional to 131.78, 181.80 and 80 is: 110.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    131.78 : 181.80 = 80 : x
  2. Step 2: Convert to fraction form
    131.78/181.80 = 80/x
  3. Step 3: Cross multiply
    131.78x = 181.80 × 80
  4. Step 4: Simplify right side
    131.78x = 14,544
  5. Step 5: Solve for x
    x = 14,544/131.78
  6. Step 6: Final answer
    x = 110.37

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.