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Finding the Fourth Proportional to 427.87, 641.85 and 245.21

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Solution

The fourth proportional to 427.87, 641.85 and 245.21 is: 367.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.87 : 641.85 = 245.21 : x
  2. Step 2: Convert to fraction form
    427.87/641.85 = 245.21/x
  3. Step 3: Cross multiply
    427.87x = 641.85 × 245.21
  4. Step 4: Simplify right side
    427.87x = 157,386.81
  5. Step 5: Solve for x
    x = 157,386.81/427.87
  6. Step 6: Final answer
    x = 367.84

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.