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Finding the Fourth Proportional to 72.86, 109.30 and 40.76

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Solution

The fourth proportional to 72.86, 109.30 and 40.76 is: 61.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.86 : 109.30 = 40.76 : x
  2. Step 2: Convert to fraction form
    72.86/109.30 = 40.76/x
  3. Step 3: Cross multiply
    72.86x = 109.30 × 40.76
  4. Step 4: Simplify right side
    72.86x = 4,455.07
  5. Step 5: Solve for x
    x = 4,455.07/72.86
  6. Step 6: Final answer
    x = 61.15

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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.