Home / 1,279.15-1,918.76-611.91

Finding the Fourth Proportional to 1,279.15, 1,918.76 and 611.91

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Solution

The fourth proportional to 1,279.15, 1,918.76 and 611.91 is: 917.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.15 : 1,918.76 = 611.91 : x
  2. Step 2: Convert to fraction form
    1,279.15/1,918.76 = 611.91/x
  3. Step 3: Cross multiply
    1,279.15x = 1,918.76 × 611.91
  4. Step 4: Simplify right side
    1,279.15x = 1,174,105.37
  5. Step 5: Solve for x
    x = 1,174,105.37/1,279.15
  6. Step 6: Final answer
    x = 917.88

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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.