Home / 1,279.19-1,919.40-621.62

Finding the Fourth Proportional to 1,279.19, 1,919.40 and 621.62

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Solution

The fourth proportional to 1,279.19, 1,919.40 and 621.62 is: 932.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.19 : 1,919.40 = 621.62 : x
  2. Step 2: Convert to fraction form
    1,279.19/1,919.40 = 621.62/x
  3. Step 3: Cross multiply
    1,279.19x = 1,919.40 × 621.62
  4. Step 4: Simplify right side
    1,279.19x = 1,193,139.90
  5. Step 5: Solve for x
    x = 1,193,139.90/1,279.19
  6. Step 6: Final answer
    x = 932.73

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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.