Home / 1,319.61-1,979.81-395.20

Finding the Fourth Proportional to 1,319.61, 1,979.81 and 395.20

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Solution

The fourth proportional to 1,319.61, 1,979.81 and 395.20 is: 592.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,319.61 : 1,979.81 = 395.20 : x
  2. Step 2: Convert to fraction form
    1,319.61/1,979.81 = 395.20/x
  3. Step 3: Cross multiply
    1,319.61x = 1,979.81 × 395.20
  4. Step 4: Simplify right side
    1,319.61x = 782,413.99
  5. Step 5: Solve for x
    x = 782,413.99/1,319.61
  6. Step 6: Final answer
    x = 592.91

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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.