Home / 1,278.60-1,917.72-412.80

Finding the Fourth Proportional to 1,278.60, 1,917.72 and 412.80

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Solution

The fourth proportional to 1,278.60, 1,917.72 and 412.80 is: 619.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.60 : 1,917.72 = 412.80 : x
  2. Step 2: Convert to fraction form
    1,278.60/1,917.72 = 412.80/x
  3. Step 3: Cross multiply
    1,278.60x = 1,917.72 × 412.80
  4. Step 4: Simplify right side
    1,278.60x = 791,634.82
  5. Step 5: Solve for x
    x = 791,634.82/1,278.60
  6. Step 6: Final answer
    x = 619.14

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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.