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Finding the Fourth Proportional to 420.34, 628.28 and 379.12

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Solution

The fourth proportional to 420.34, 628.28 and 379.12 is: 566.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.34 : 628.28 = 379.12 : x
  2. Step 2: Convert to fraction form
    420.34/628.28 = 379.12/x
  3. Step 3: Cross multiply
    420.34x = 628.28 × 379.12
  4. Step 4: Simplify right side
    420.34x = 238,193.51
  5. Step 5: Solve for x
    x = 238,193.51/420.34
  6. Step 6: Final answer
    x = 566.67

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.