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Finding the Fourth Proportional to 72.79, 109.28 and 52.28

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Solution

The fourth proportional to 72.79, 109.28 and 52.28 is: 78.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.79 : 109.28 = 52.28 : x
  2. Step 2: Convert to fraction form
    72.79/109.28 = 52.28/x
  3. Step 3: Cross multiply
    72.79x = 109.28 × 52.28
  4. Step 4: Simplify right side
    72.79x = 5,713.16
  5. Step 5: Solve for x
    x = 5,713.16/72.79
  6. Step 6: Final answer
    x = 78.49

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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.