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Finding the Fourth Proportional to 8,438.40, 12,657.60 and 8,380.80

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Solution

The fourth proportional to 8,438.40, 12,657.60 and 8,380.80 is: 12,571.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    8,438.40 : 12,657.60 = 8,380.80 : x
  2. Step 2: Convert to fraction form
    8,438.40/12,657.60 = 8,380.80/x
  3. Step 3: Cross multiply
    8,438.40x = 12,657.60 × 8,380.80
  4. Step 4: Simplify right side
    8,438.40x = 106,080,814.08
  5. Step 5: Solve for x
    x = 106,080,814.08/8,438.40
  6. Step 6: Final answer
    x = 12,571.20

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Similar ratio
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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.