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Finding the Fourth Proportional to 518.85, 715.70 and 378.80

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Solution

The fourth proportional to 518.85, 715.70 and 378.80 is: 522.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.85 : 715.70 = 378.80 : x
  2. Step 2: Convert to fraction form
    518.85/715.70 = 378.80/x
  3. Step 3: Cross multiply
    518.85x = 715.70 × 378.80
  4. Step 4: Simplify right side
    518.85x = 271,104.37
  5. Step 5: Solve for x
    x = 271,104.37/518.85
  6. Step 6: Final answer
    x = 522.51

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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.