Home / 1,278.61-1,917.89-509.11

Finding the Fourth Proportional to 1,278.61, 1,917.89 and 509.11

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Solution

The fourth proportional to 1,278.61, 1,917.89 and 509.11 is: 763.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.61 : 1,917.89 = 509.11 : x
  2. Step 2: Convert to fraction form
    1,278.61/1,917.89 = 509.11/x
  3. Step 3: Cross multiply
    1,278.61x = 1,917.89 × 509.11
  4. Step 4: Simplify right side
    1,278.61x = 976,404.84
  5. Step 5: Solve for x
    x = 976,404.84/1,278.61
  6. Step 6: Final answer
    x = 763.65

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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.