Home / 1,278.19-1,917.30-412.51

Finding the Fourth Proportional to 1,278.19, 1,917.30 and 412.51

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Solution

The fourth proportional to 1,278.19, 1,917.30 and 412.51 is: 618.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.19 : 1,917.30 = 412.51 : x
  2. Step 2: Convert to fraction form
    1,278.19/1,917.30 = 412.51/x
  3. Step 3: Cross multiply
    1,278.19x = 1,917.30 × 412.51
  4. Step 4: Simplify right side
    1,278.19x = 790,905.42
  5. Step 5: Solve for x
    x = 790,905.42/1,278.19
  6. Step 6: Final answer
    x = 618.77

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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.