Home / 1,278.18-1,915.49-619.79

Finding the Fourth Proportional to 1,278.18, 1,915.49 and 619.79

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Solution

The fourth proportional to 1,278.18, 1,915.49 and 619.79 is: 928.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.18 : 1,915.49 = 619.79 : x
  2. Step 2: Convert to fraction form
    1,278.18/1,915.49 = 619.79/x
  3. Step 3: Cross multiply
    1,278.18x = 1,915.49 × 619.79
  4. Step 4: Simplify right side
    1,278.18x = 1,187,191.97
  5. Step 5: Solve for x
    x = 1,187,191.97/1,278.18
  6. Step 6: Final answer
    x = 928.81

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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.