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Finding the Fourth Proportional to 620.85, 856.53 and 372.09

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Solution

The fourth proportional to 620.85, 856.53 and 372.09 is: 513.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.85 : 856.53 = 372.09 : x
  2. Step 2: Convert to fraction form
    620.85/856.53 = 372.09/x
  3. Step 3: Cross multiply
    620.85x = 856.53 × 372.09
  4. Step 4: Simplify right side
    620.85x = 318,706.25
  5. Step 5: Solve for x
    x = 318,706.25/620.85
  6. Step 6: Final answer
    x = 513.34

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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.