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Finding the Fourth Proportional to 342.70, 514.03 and 86.20

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Solution

The fourth proportional to 342.70, 514.03 and 86.20 is: 129.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.70 : 514.03 = 86.20 : x
  2. Step 2: Convert to fraction form
    342.70/514.03 = 86.20/x
  3. Step 3: Cross multiply
    342.70x = 514.03 × 86.20
  4. Step 4: Simplify right side
    342.70x = 44,309.39
  5. Step 5: Solve for x
    x = 44,309.39/342.70
  6. Step 6: Final answer
    x = 129.29

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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.