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Finding the Third Proportional to 420.19 and 860.63

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Solution

The third proportional to 420.19 and 860.63 is: 1,762.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.19 : 860.63 = 860.63 : x
  2. Step 2: Convert to fraction form
    420.19/860.63 = 860.63/x
  3. Step 3: Cross multiply
    420.19x = 860.63 × 860.63
  4. Step 4: Simplify right side
    420.19x = 740,675.39
  5. Step 5: Solve for x
    x = 740,675.39/420.19
  6. Step 6: Final answer
    x = 1,762.73

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1.5x scale

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.