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Finding the Fourth Proportional to 684.86, 945.14 and 405.15

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Solution

The fourth proportional to 684.86, 945.14 and 405.15 is: 559.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.86 : 945.14 = 405.15 : x
  2. Step 2: Convert to fraction form
    684.86/945.14 = 405.15/x
  3. Step 3: Cross multiply
    684.86x = 945.14 × 405.15
  4. Step 4: Simplify right side
    684.86x = 382,926.64
  5. Step 5: Solve for x
    x = 382,926.64/684.86
  6. Step 6: Final answer
    x = 559.13

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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.