Home / 1,279.40-1,917.80-498.91

Finding the Fourth Proportional to 1,279.40, 1,917.80 and 498.91

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Solution

The fourth proportional to 1,279.40, 1,917.80 and 498.91 is: 747.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.40 : 1,917.80 = 498.91 : x
  2. Step 2: Convert to fraction form
    1,279.40/1,917.80 = 498.91/x
  3. Step 3: Cross multiply
    1,279.40x = 1,917.80 × 498.91
  4. Step 4: Simplify right side
    1,279.40x = 956,809.60
  5. Step 5: Solve for x
    x = 956,809.60/1,279.40
  6. Step 6: Final answer
    x = 747.86

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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.