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Finding the Fourth Proportional to 43.90, 65.80 and 30.39

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Solution

The fourth proportional to 43.90, 65.80 and 30.39 is: 45.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    43.90 : 65.80 = 30.39 : x
  2. Step 2: Convert to fraction form
    43.90/65.80 = 30.39/x
  3. Step 3: Cross multiply
    43.90x = 65.80 × 30.39
  4. Step 4: Simplify right side
    43.90x = 1,999.66
  5. Step 5: Solve for x
    x = 1,999.66/43.90
  6. Step 6: Final answer
    x = 45.55

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.