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Finding the Fourth Proportional to 50.80, 75.80 and 45.90

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Solution

The fourth proportional to 50.80, 75.80 and 45.90 is: 68.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    50.80 : 75.80 = 45.90 : x
  2. Step 2: Convert to fraction form
    50.80/75.80 = 45.90/x
  3. Step 3: Cross multiply
    50.80x = 75.80 × 45.90
  4. Step 4: Simplify right side
    50.80x = 3,479.22
  5. Step 5: Solve for x
    x = 3,479.22/50.80
  6. Step 6: Final answer
    x = 68.49

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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.