Home / 1,420.36-2,131.07-640.13

Finding the Fourth Proportional to 1,420.36, 2,131.07 and 640.13

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Solution

The fourth proportional to 1,420.36, 2,131.07 and 640.13 is: 960.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,420.36 : 2,131.07 = 640.13 : x
  2. Step 2: Convert to fraction form
    1,420.36/2,131.07 = 640.13/x
  3. Step 3: Cross multiply
    1,420.36x = 2,131.07 × 640.13
  4. Step 4: Simplify right side
    1,420.36x = 1,364,163.44
  5. Step 5: Solve for x
    x = 1,364,163.44/1,420.36
  6. Step 6: Final answer
    x = 960.43

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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.