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Finding the Fourth Proportional to 620.31, 856.10 and 371.79

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Solution

The fourth proportional to 620.31, 856.10 and 371.79 is: 513.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.31 : 856.10 = 371.79 : x
  2. Step 2: Convert to fraction form
    620.31/856.10 = 371.79/x
  3. Step 3: Cross multiply
    620.31x = 856.10 × 371.79
  4. Step 4: Simplify right side
    620.31x = 318,290.35
  5. Step 5: Solve for x
    x = 318,290.35/620.31
  6. Step 6: Final answer
    x = 513.12

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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.