Home / 1,380.38-2,070.90-406.49

Finding the Fourth Proportional to 1,380.38, 2,070.90 and 406.49

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Solution

The fourth proportional to 1,380.38, 2,070.90 and 406.49 is: 609.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,380.38 : 2,070.90 = 406.49 : x
  2. Step 2: Convert to fraction form
    1,380.38/2,070.90 = 406.49/x
  3. Step 3: Cross multiply
    1,380.38x = 2,070.90 × 406.49
  4. Step 4: Simplify right side
    1,380.38x = 841,789.79
  5. Step 5: Solve for x
    x = 841,789.79/1,380.38
  6. Step 6: Final answer
    x = 609.83

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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.