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Finding the Fourth Proportional to 72.68, 100.30 and 39.93

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Solution

The fourth proportional to 72.68, 100.30 and 39.93 is: 55.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.68 : 100.30 = 39.93 : x
  2. Step 2: Convert to fraction form
    72.68/100.30 = 39.93/x
  3. Step 3: Cross multiply
    72.68x = 100.30 × 39.93
  4. Step 4: Simplify right side
    72.68x = 4,004.98
  5. Step 5: Solve for x
    x = 4,004.98/72.68
  6. Step 6: Final answer
    x = 55.11

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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.