Home / 1,380.09-2,070.21-406.20

Finding the Fourth Proportional to 1,380.09, 2,070.21 and 406.20

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Solution

The fourth proportional to 1,380.09, 2,070.21 and 406.20 is: 609.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,380.09 : 2,070.21 = 406.20 : x
  2. Step 2: Convert to fraction form
    1,380.09/2,070.21 = 406.20/x
  3. Step 3: Cross multiply
    1,380.09x = 2,070.21 × 406.20
  4. Step 4: Simplify right side
    1,380.09x = 840,919.30
  5. Step 5: Solve for x
    x = 840,919.30/1,380.09
  6. Step 6: Final answer
    x = 609.32

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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.