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Finding the Fourth Proportional to 72.51, 100.23 and 54.21

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Solution

The fourth proportional to 72.51, 100.23 and 54.21 is: 74.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.51 : 100.23 = 54.21 : x
  2. Step 2: Convert to fraction form
    72.51/100.23 = 54.21/x
  3. Step 3: Cross multiply
    72.51x = 100.23 × 54.21
  4. Step 4: Simplify right side
    72.51x = 5,433.47
  5. Step 5: Solve for x
    x = 5,433.47/72.51
  6. Step 6: Final answer
    x = 74.93

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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.