Home / 12,990.40-19,485.60-8,000.80

Finding the Fourth Proportional to 12,990.40, 19,485.60 and 8,000.80

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Solution

The fourth proportional to 12,990.40, 19,485.60 and 8,000.80 is: 12,001.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    12,990.40 : 19,485.60 = 8,000.80 : x
  2. Step 2: Convert to fraction form
    12,990.40/19,485.60 = 8,000.80/x
  3. Step 3: Cross multiply
    12,990.40x = 19,485.60 × 8,000.80
  4. Step 4: Simplify right side
    12,990.40x = 155,900,388.48
  5. Step 5: Solve for x
    x = 155,900,388.48/12,990.40
  6. Step 6: Final answer
    x = 12,001.20

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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.