Home / 1,328.30-1,991.19-669.74

Finding the Fourth Proportional to 1,328.30, 1,991.19 and 669.74

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Solution

The fourth proportional to 1,328.30, 1,991.19 and 669.74 is: 1,003.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,328.30 : 1,991.19 = 669.74 : x
  2. Step 2: Convert to fraction form
    1,328.30/1,991.19 = 669.74/x
  3. Step 3: Cross multiply
    1,328.30x = 1,991.19 × 669.74
  4. Step 4: Simplify right side
    1,328.30x = 1,333,579.59
  5. Step 5: Solve for x
    x = 1,333,579.59/1,328.30
  6. Step 6: Final answer
    x = 1,003.97

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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.