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Finding the Fourth Proportional to 518.50, 715.26 and 308.80

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Solution

The fourth proportional to 518.50, 715.26 and 308.80 is: 425.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.50 : 715.26 = 308.80 : x
  2. Step 2: Convert to fraction form
    518.50/715.26 = 308.80/x
  3. Step 3: Cross multiply
    518.50x = 715.26 × 308.80
  4. Step 4: Simplify right side
    518.50x = 220,872.29
  5. Step 5: Solve for x
    x = 220,872.29/518.50
  6. Step 6: Final answer
    x = 425.98

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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.