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Finding the Fourth Proportional to 2,120.70, 3,181.35 and 659.70

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Solution

The fourth proportional to 2,120.70, 3,181.35 and 659.70 is: 989.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,120.70 : 3,181.35 = 659.70 : x
  2. Step 2: Convert to fraction form
    2,120.70/3,181.35 = 659.70/x
  3. Step 3: Cross multiply
    2,120.70x = 3,181.35 × 659.70
  4. Step 4: Simplify right side
    2,120.70x = 2,098,736.60
  5. Step 5: Solve for x
    x = 2,098,736.60/2,120.70
  6. Step 6: Final answer
    x = 989.64

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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.