Home / 1,279.20-1,918.78-457.56

Finding the Fourth Proportional to 1,279.20, 1,918.78 and 457.56

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Solution

The fourth proportional to 1,279.20, 1,918.78 and 457.56 is: 686.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.20 : 1,918.78 = 457.56 : x
  2. Step 2: Convert to fraction form
    1,279.20/1,918.78 = 457.56/x
  3. Step 3: Cross multiply
    1,279.20x = 1,918.78 × 457.56
  4. Step 4: Simplify right side
    1,279.20x = 877,956.98
  5. Step 5: Solve for x
    x = 877,956.98/1,279.20
  6. Step 6: Final answer
    x = 686.33

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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.