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Finding the Fourth Proportional to 684.80, 945.15 and 518.74

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Solution

The fourth proportional to 684.80, 945.15 and 518.74 is: 715.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.80 : 945.15 = 518.74 : x
  2. Step 2: Convert to fraction form
    684.80/945.15 = 518.74/x
  3. Step 3: Cross multiply
    684.80x = 945.15 × 518.74
  4. Step 4: Simplify right side
    684.80x = 490,285.72
  5. Step 5: Solve for x
    x = 490,285.72/684.80
  6. Step 6: Final answer
    x = 715.95

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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.