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Finding the Fourth Proportional to 72.89, 109.88 and 65.45

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Solution

The fourth proportional to 72.89, 109.88 and 65.45 is: 98.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.89 : 109.88 = 65.45 : x
  2. Step 2: Convert to fraction form
    72.89/109.88 = 65.45/x
  3. Step 3: Cross multiply
    72.89x = 109.88 × 65.45
  4. Step 4: Simplify right side
    72.89x = 7,191.59
  5. Step 5: Solve for x
    x = 7,191.59/72.89
  6. Step 6: Final answer
    x = 98.66

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.