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Finding the Fourth Proportional to 130.56, 180.04 and 78.80

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Solution

The fourth proportional to 130.56, 180.04 and 78.80 is: 108.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.56 : 180.04 = 78.80 : x
  2. Step 2: Convert to fraction form
    130.56/180.04 = 78.80/x
  3. Step 3: Cross multiply
    130.56x = 180.04 × 78.80
  4. Step 4: Simplify right side
    130.56x = 14,187.15
  5. Step 5: Solve for x
    x = 14,187.15/130.56
  6. Step 6: Final answer
    x = 108.66

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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.