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Finding the Fourth Proportional to 711.53, 981.93 and 396.80

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Solution

The fourth proportional to 711.53, 981.93 and 396.80 is: 547.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    711.53 : 981.93 = 396.80 : x
  2. Step 2: Convert to fraction form
    711.53/981.93 = 396.80/x
  3. Step 3: Cross multiply
    711.53x = 981.93 × 396.80
  4. Step 4: Simplify right side
    711.53x = 389,629.82
  5. Step 5: Solve for x
    x = 389,629.82/711.53
  6. Step 6: Final answer
    x = 547.59

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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.