Home / 1,389.80-2,083.42-619.88

Finding the Fourth Proportional to 1,389.80, 2,083.42 and 619.88

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Solution

The fourth proportional to 1,389.80, 2,083.42 and 619.88 is: 929.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.80 : 2,083.42 = 619.88 : x
  2. Step 2: Convert to fraction form
    1,389.80/2,083.42 = 619.88/x
  3. Step 3: Cross multiply
    1,389.80x = 2,083.42 × 619.88
  4. Step 4: Simplify right side
    1,389.80x = 1,291,470.39
  5. Step 5: Solve for x
    x = 1,291,470.39/1,389.80
  6. Step 6: Final answer
    x = 929.25

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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.