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Finding the Fourth Proportional to 130.55, 180.20 and 78.13

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Solution

The fourth proportional to 130.55, 180.20 and 78.13 is: 107.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.55 : 180.20 = 78.13 : x
  2. Step 2: Convert to fraction form
    130.55/180.20 = 78.13/x
  3. Step 3: Cross multiply
    130.55x = 180.20 × 78.13
  4. Step 4: Simplify right side
    130.55x = 14,079.03
  5. Step 5: Solve for x
    x = 14,079.03/130.55
  6. Step 6: Final answer
    x = 107.84

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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.