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Finding the Fourth Proportional to 620.78, 856.64 and 371.95

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Solution

The fourth proportional to 620.78, 856.64 and 371.95 is: 513.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.78 : 856.64 = 371.95 : x
  2. Step 2: Convert to fraction form
    620.78/856.64 = 371.95/x
  3. Step 3: Cross multiply
    620.78x = 856.64 × 371.95
  4. Step 4: Simplify right side
    620.78x = 318,626.04
  5. Step 5: Solve for x
    x = 318,626.04/620.78
  6. Step 6: Final answer
    x = 513.27

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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.