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Finding the Fourth Proportional to 80.55, 111.20 and 47.81

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Solution

The fourth proportional to 80.55, 111.20 and 47.81 is: 66.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.55 : 111.20 = 47.81 : x
  2. Step 2: Convert to fraction form
    80.55/111.20 = 47.81/x
  3. Step 3: Cross multiply
    80.55x = 111.20 × 47.81
  4. Step 4: Simplify right side
    80.55x = 5,316.51
  5. Step 5: Solve for x
    x = 5,316.51/80.55
  6. Step 6: Final answer
    x = 66.00

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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.