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Finding the Fourth Proportional to 620.39, 855.99 and 371.81

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Solution

The fourth proportional to 620.39, 855.99 and 371.81 is: 513.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.39 : 855.99 = 371.81 : x
  2. Step 2: Convert to fraction form
    620.39/855.99 = 371.81/x
  3. Step 3: Cross multiply
    620.39x = 855.99 × 371.81
  4. Step 4: Simplify right side
    620.39x = 318,267.78
  5. Step 5: Solve for x
    x = 318,267.78/620.39
  6. Step 6: Final answer
    x = 513.01

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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.