Home / 1,278.24-1,917.37-388.78

Finding the Fourth Proportional to 1,278.24, 1,917.37 and 388.78

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Solution

The fourth proportional to 1,278.24, 1,917.37 and 388.78 is: 583.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.24 : 1,917.37 = 388.78 : x
  2. Step 2: Convert to fraction form
    1,278.24/1,917.37 = 388.78/x
  3. Step 3: Cross multiply
    1,278.24x = 1,917.37 × 388.78
  4. Step 4: Simplify right side
    1,278.24x = 745,428.61
  5. Step 5: Solve for x
    x = 745,428.61/1,278.24
  6. Step 6: Final answer
    x = 583.17

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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.