Home / 1,387.17-2,080.40-413.05

Finding the Fourth Proportional to 1,387.17, 2,080.40 and 413.05

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Solution

The fourth proportional to 1,387.17, 2,080.40 and 413.05 is: 619.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,387.17 : 2,080.40 = 413.05 : x
  2. Step 2: Convert to fraction form
    1,387.17/2,080.40 = 413.05/x
  3. Step 3: Cross multiply
    1,387.17x = 2,080.40 × 413.05
  4. Step 4: Simplify right side
    1,387.17x = 859,309.22
  5. Step 5: Solve for x
    x = 859,309.22/1,387.17
  6. Step 6: Final answer
    x = 619.47

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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.