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Finding the Third Proportional to 420.19 and 859.57

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Solution

The third proportional to 420.19 and 859.57 is: 1,758.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.19 : 859.57 = 859.57 : x
  2. Step 2: Convert to fraction form
    420.19/859.57 = 859.57/x
  3. Step 3: Cross multiply
    420.19x = 859.57 × 859.57
  4. Step 4: Simplify right side
    420.19x = 738,861.12
  5. Step 5: Solve for x
    x = 738,861.12/420.19
  6. Step 6: Final answer
    x = 1,758.41

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Why These Related Problems?

These problems maintain the same ratio (2.05) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.