Home / 1,278.66-1,918.20-412.86

Finding the Fourth Proportional to 1,278.66, 1,918.20 and 412.86

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Solution

The fourth proportional to 1,278.66, 1,918.20 and 412.86 is: 619.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.66 : 1,918.20 = 412.86 : x
  2. Step 2: Convert to fraction form
    1,278.66/1,918.20 = 412.86/x
  3. Step 3: Cross multiply
    1,278.66x = 1,918.20 × 412.86
  4. Step 4: Simplify right side
    1,278.66x = 791,948.05
  5. Step 5: Solve for x
    x = 791,948.05/1,278.66
  6. Step 6: Final answer
    x = 619.36

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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.