Home / 1,319.21-1,979.10-394.85

Finding the Fourth Proportional to 1,319.21, 1,979.10 and 394.85

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Solution

The fourth proportional to 1,319.21, 1,979.10 and 394.85 is: 592.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.21 : 1,979.10 = 394.85 : x
  2. Step 2: Convert to fraction form
    1,319.21/1,979.10 = 394.85/x
  3. Step 3: Cross multiply
    1,319.21x = 1,979.10 × 394.85
  4. Step 4: Simplify right side
    1,319.21x = 781,437.74
  5. Step 5: Solve for x
    x = 781,437.74/1,319.21
  6. Step 6: Final answer
    x = 592.36

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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.