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Finding the Fourth Proportional to 72.86, 109.16 and 70.19

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Solution

The fourth proportional to 72.86, 109.16 and 70.19 is: 105.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.86 : 109.16 = 70.19 : x
  2. Step 2: Convert to fraction form
    72.86/109.16 = 70.19/x
  3. Step 3: Cross multiply
    72.86x = 109.16 × 70.19
  4. Step 4: Simplify right side
    72.86x = 7,661.86
  5. Step 5: Solve for x
    x = 7,661.86/72.86
  6. Step 6: Final answer
    x = 105.17

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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.