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Finding the Fourth Proportional to 40.50, 56 and 38.80

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Solution

The fourth proportional to 40.50, 56 and 38.80 is: 53.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    40.50 : 56 = 38.80 : x
  2. Step 2: Convert to fraction form
    40.50/56 = 38.80/x
  3. Step 3: Cross multiply
    40.50x = 56 × 38.80
  4. Step 4: Simplify right side
    40.50x = 2,172.80
  5. Step 5: Solve for x
    x = 2,172.80/40.50
  6. Step 6: Final answer
    x = 53.65

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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.