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Finding the Fourth Proportional to 628.89, 867.87 and 380.19

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Solution

The fourth proportional to 628.89, 867.87 and 380.19 is: 524.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.89 : 867.87 = 380.19 : x
  2. Step 2: Convert to fraction form
    628.89/867.87 = 380.19/x
  3. Step 3: Cross multiply
    628.89x = 867.87 × 380.19
  4. Step 4: Simplify right side
    628.89x = 329,958.75
  5. Step 5: Solve for x
    x = 329,958.75/628.89
  6. Step 6: Final answer
    x = 524.67

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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.