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Finding the Fourth Proportional to 1,081.20, 1,621.62 and 838.20

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Solution

The fourth proportional to 1,081.20, 1,621.62 and 838.20 is: 1,257.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,081.20 : 1,621.62 = 838.20 : x
  2. Step 2: Convert to fraction form
    1,081.20/1,621.62 = 838.20/x
  3. Step 3: Cross multiply
    1,081.20x = 1,621.62 × 838.20
  4. Step 4: Simplify right side
    1,081.20x = 1,359,241.88
  5. Step 5: Solve for x
    x = 1,359,241.88/1,081.20
  6. Step 6: Final answer
    x = 1,257.16

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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.