Home / 1,278.58-1,917.51-412.42

Finding the Fourth Proportional to 1,278.58, 1,917.51 and 412.42

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Solution

The fourth proportional to 1,278.58, 1,917.51 and 412.42 is: 618.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.58 : 1,917.51 = 412.42 : x
  2. Step 2: Convert to fraction form
    1,278.58/1,917.51 = 412.42/x
  3. Step 3: Cross multiply
    1,278.58x = 1,917.51 × 412.42
  4. Step 4: Simplify right side
    1,278.58x = 790,819.47
  5. Step 5: Solve for x
    x = 790,819.47/1,278.58
  6. Step 6: Final answer
    x = 618.51

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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.