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Finding the Fourth Proportional to 72.85, 100.29 and 63.15

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Solution

The fourth proportional to 72.85, 100.29 and 63.15 is: 86.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.85 : 100.29 = 63.15 : x
  2. Step 2: Convert to fraction form
    72.85/100.29 = 63.15/x
  3. Step 3: Cross multiply
    72.85x = 100.29 × 63.15
  4. Step 4: Simplify right side
    72.85x = 6,333.03
  5. Step 5: Solve for x
    x = 6,333.03/72.85
  6. Step 6: Final answer
    x = 86.93

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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.