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Finding the Fourth Proportional to 51.29, 70.78 and 30.57

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Solution

The fourth proportional to 51.29, 70.78 and 30.57 is: 42.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.29 : 70.78 = 30.57 : x
  2. Step 2: Convert to fraction form
    51.29/70.78 = 30.57/x
  3. Step 3: Cross multiply
    51.29x = 70.78 × 30.57
  4. Step 4: Simplify right side
    51.29x = 2,163.31
  5. Step 5: Solve for x
    x = 2,163.31/51.29
  6. Step 6: Final answer
    x = 42.18

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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.