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Finding the Fourth Proportional to 51.30, 70.83 and 42.21

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Solution

The fourth proportional to 51.30, 70.83 and 42.21 is: 58.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.30 : 70.83 = 42.21 : x
  2. Step 2: Convert to fraction form
    51.30/70.83 = 42.21/x
  3. Step 3: Cross multiply
    51.30x = 70.83 × 42.21
  4. Step 4: Simplify right side
    51.30x = 2,989.73
  5. Step 5: Solve for x
    x = 2,989.73/51.30
  6. Step 6: Final answer
    x = 58.28

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.