Home / 1,319.82-1,979.61-345.90

Finding the Fourth Proportional to 1,319.82, 1,979.61 and 345.90

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Solution

The fourth proportional to 1,319.82, 1,979.61 and 345.90 is: 518.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.82 : 1,979.61 = 345.90 : x
  2. Step 2: Convert to fraction form
    1,319.82/1,979.61 = 345.90/x
  3. Step 3: Cross multiply
    1,319.82x = 1,979.61 × 345.90
  4. Step 4: Simplify right side
    1,319.82x = 684,747.10
  5. Step 5: Solve for x
    x = 684,747.10/1,319.82
  6. Step 6: Final answer
    x = 518.82

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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.