Home / 1,326.20-1,989.30-1,239.80

Finding the Fourth Proportional to 1,326.20, 1,989.30 and 1,239.80

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Solution

The fourth proportional to 1,326.20, 1,989.30 and 1,239.80 is: 1,859.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,326.20 : 1,989.30 = 1,239.80 : x
  2. Step 2: Convert to fraction form
    1,326.20/1,989.30 = 1,239.80/x
  3. Step 3: Cross multiply
    1,326.20x = 1,989.30 × 1,239.80
  4. Step 4: Simplify right side
    1,326.20x = 2,466,334.14
  5. Step 5: Solve for x
    x = 2,466,334.14/1,326.20
  6. Step 6: Final answer
    x = 1,859.70

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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.