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Finding the Fourth Proportional to 51.80, 77.28 and 45.80

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Solution

The fourth proportional to 51.80, 77.28 and 45.80 is: 68.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.80 : 77.28 = 45.80 : x
  2. Step 2: Convert to fraction form
    51.80/77.28 = 45.80/x
  3. Step 3: Cross multiply
    51.80x = 77.28 × 45.80
  4. Step 4: Simplify right side
    51.80x = 3,539.20
  5. Step 5: Solve for x
    x = 3,539.20/51.80
  6. Step 6: Final answer
    x = 68.32

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.