Home / 1,279.10-1,764.66-780.88

Finding the Fourth Proportional to 1,279.10, 1,764.66 and 780.88

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Solution

The fourth proportional to 1,279.10, 1,764.66 and 780.88 is: 1,077.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.10 : 1,764.66 = 780.88 : x
  2. Step 2: Convert to fraction form
    1,279.10/1,764.66 = 780.88/x
  3. Step 3: Cross multiply
    1,279.10x = 1,764.66 × 780.88
  4. Step 4: Simplify right side
    1,279.10x = 1,377,987.70
  5. Step 5: Solve for x
    x = 1,377,987.70/1,279.10
  6. Step 6: Final answer
    x = 1,077.31

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.