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Finding the Fourth Proportional to 56, 77.30 and 38.80

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Solution

The fourth proportional to 56, 77.30 and 38.80 is: 53.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    56 : 77.30 = 38.80 : x
  2. Step 2: Convert to fraction form
    56/77.30 = 38.80/x
  3. Step 3: Cross multiply
    56x = 77.30 × 38.80
  4. Step 4: Simplify right side
    56x = 2,999.24
  5. Step 5: Solve for x
    x = 2,999.24/56
  6. Step 6: Final answer
    x = 53.56

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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.