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Finding the Fourth Proportional to 40, 55.44 and 39.80

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Solution

The fourth proportional to 40, 55.44 and 39.80 is: 55.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    40 : 55.44 = 39.80 : x
  2. Step 2: Convert to fraction form
    40/55.44 = 39.80/x
  3. Step 3: Cross multiply
    40x = 55.44 × 39.80
  4. Step 4: Simplify right side
    40x = 2,206.51
  5. Step 5: Solve for x
    x = 2,206.51/40
  6. Step 6: Final answer
    x = 55.16

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.