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Finding the Fourth Proportional to 342.78, 514.20 and 265.80

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Solution

The fourth proportional to 342.78, 514.20 and 265.80 is: 398.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.78 : 514.20 = 265.80 : x
  2. Step 2: Convert to fraction form
    342.78/514.20 = 265.80/x
  3. Step 3: Cross multiply
    342.78x = 514.20 × 265.80
  4. Step 4: Simplify right side
    342.78x = 136,674.36
  5. Step 5: Solve for x
    x = 136,674.36/342.78
  6. Step 6: Final answer
    x = 398.72

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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.