Home / 1,278.55-1,917.87-412.75

Finding the Fourth Proportional to 1,278.55, 1,917.87 and 412.75

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Solution

The fourth proportional to 1,278.55, 1,917.87 and 412.75 is: 619.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.55 : 1,917.87 = 412.75 : x
  2. Step 2: Convert to fraction form
    1,278.55/1,917.87 = 412.75/x
  3. Step 3: Cross multiply
    1,278.55x = 1,917.87 × 412.75
  4. Step 4: Simplify right side
    1,278.55x = 791,600.84
  5. Step 5: Solve for x
    x = 791,600.84/1,278.55
  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.