Home / 1,279.35-1,761.48-1,129.86

Finding the Fourth Proportional to 1,279.35, 1,761.48 and 1,129.86

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Solution

The fourth proportional to 1,279.35, 1,761.48 and 1,129.86 is: 1,555.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.35 : 1,761.48 = 1,129.86 : x
  2. Step 2: Convert to fraction form
    1,279.35/1,761.48 = 1,129.86/x
  3. Step 3: Cross multiply
    1,279.35x = 1,761.48 × 1,129.86
  4. Step 4: Simplify right side
    1,279.35x = 1,990,225.79
  5. Step 5: Solve for x
    x = 1,990,225.79/1,279.35
  6. Step 6: Final answer
    x = 1,555.65

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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.