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Finding the Fourth Proportional to 686.03, 945.30 and 611.56

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Solution

The fourth proportional to 686.03, 945.30 and 611.56 is: 842.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.03 : 945.30 = 611.56 : x
  2. Step 2: Convert to fraction form
    686.03/945.30 = 611.56/x
  3. Step 3: Cross multiply
    686.03x = 945.30 × 611.56
  4. Step 4: Simplify right side
    686.03x = 578,107.67
  5. Step 5: Solve for x
    x = 578,107.67/686.03
  6. Step 6: Final answer
    x = 842.69

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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.