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Finding the Fourth Proportional to 72.63, 100.23 and 39.88

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Solution

The fourth proportional to 72.63, 100.23 and 39.88 is: 55.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.63 : 100.23 = 39.88 : x
  2. Step 2: Convert to fraction form
    72.63/100.23 = 39.88/x
  3. Step 3: Cross multiply
    72.63x = 100.23 × 39.88
  4. Step 4: Simplify right side
    72.63x = 3,996.97
  5. Step 5: Solve for x
    x = 3,996.97/72.63
  6. Step 6: Final answer
    x = 55.03

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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.