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Finding the Fourth Proportional to 51.20, 76.80 and 43.50

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Solution

The fourth proportional to 51.20, 76.80 and 43.50 is: 65.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.20 : 76.80 = 43.50 : x
  2. Step 2: Convert to fraction form
    51.20/76.80 = 43.50/x
  3. Step 3: Cross multiply
    51.20x = 76.80 × 43.50
  4. Step 4: Simplify right side
    51.20x = 3,340.80
  5. Step 5: Solve for x
    x = 3,340.80/51.20
  6. Step 6: Final answer
    x = 65.25

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.