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Finding the Fourth Proportional to 1,216.20, 1,821.10 and 889.80

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Solution

The fourth proportional to 1,216.20, 1,821.10 and 889.80 is: 1,332.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,216.20 : 1,821.10 = 889.80 : x
  2. Step 2: Convert to fraction form
    1,216.20/1,821.10 = 889.80/x
  3. Step 3: Cross multiply
    1,216.20x = 1,821.10 × 889.80
  4. Step 4: Simplify right side
    1,216.20x = 1,620,414.78
  5. Step 5: Solve for x
    x = 1,620,414.78/1,216.20
  6. Step 6: Final answer
    x = 1,332.36

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1.5x scale

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.