Home / 1,292.79-1,939.17-318.90

Finding the Fourth Proportional to 1,292.79, 1,939.17 and 318.90

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Solution

The fourth proportional to 1,292.79, 1,939.17 and 318.90 is: 478.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,292.79 : 1,939.17 = 318.90 : x
  2. Step 2: Convert to fraction form
    1,292.79/1,939.17 = 318.90/x
  3. Step 3: Cross multiply
    1,292.79x = 1,939.17 × 318.90
  4. Step 4: Simplify right side
    1,292.79x = 618,396.47
  5. Step 5: Solve for x
    x = 618,396.47/1,292.79
  6. Step 6: Final answer
    x = 478.34

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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.