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Finding the Fourth Proportional to 55.80, 77.40 and 53.91

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Solution

The fourth proportional to 55.80, 77.40 and 53.91 is: 74.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.80 : 77.40 = 53.91 : x
  2. Step 2: Convert to fraction form
    55.80/77.40 = 53.91/x
  3. Step 3: Cross multiply
    55.80x = 77.40 × 53.91
  4. Step 4: Simplify right side
    55.80x = 4,172.63
  5. Step 5: Solve for x
    x = 4,172.63/55.80
  6. Step 6: Final answer
    x = 74.78

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.