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Finding the Fourth Proportional to 72.85, 108.70 and 70.51

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Solution

The fourth proportional to 72.85, 108.70 and 70.51 is: 105.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.85 : 108.70 = 70.51 : x
  2. Step 2: Convert to fraction form
    72.85/108.70 = 70.51/x
  3. Step 3: Cross multiply
    72.85x = 108.70 × 70.51
  4. Step 4: Simplify right side
    72.85x = 7,664.44
  5. Step 5: Solve for x
    x = 7,664.44/72.85
  6. Step 6: Final answer
    x = 105.21

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.