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Finding the Fourth Proportional to 40.79, 55.89 and 39.80

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Solution

The fourth proportional to 40.79, 55.89 and 39.80 is: 54.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.79 : 55.89 = 39.80 : x
  2. Step 2: Convert to fraction form
    40.79/55.89 = 39.80/x
  3. Step 3: Cross multiply
    40.79x = 55.89 × 39.80
  4. Step 4: Simplify right side
    40.79x = 2,224.22
  5. Step 5: Solve for x
    x = 2,224.22/40.79
  6. Step 6: Final answer
    x = 54.53

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.