Home / 1,339.19-2,009.39-690.38

Finding the Fourth Proportional to 1,339.19, 2,009.39 and 690.38

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Solution

The fourth proportional to 1,339.19, 2,009.39 and 690.38 is: 1,035.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,339.19 : 2,009.39 = 690.38 : x
  2. Step 2: Convert to fraction form
    1,339.19/2,009.39 = 690.38/x
  3. Step 3: Cross multiply
    1,339.19x = 2,009.39 × 690.38
  4. Step 4: Simplify right side
    1,339.19x = 1,387,244.39
  5. Step 5: Solve for x
    x = 1,387,244.39/1,339.19
  6. Step 6: Final answer
    x = 1,035.88

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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.