Home / 1,420.45-2,131.32-640.02

Finding the Fourth Proportional to 1,420.45, 2,131.32 and 640.02

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Solution

The fourth proportional to 1,420.45, 2,131.32 and 640.02 is: 960.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,420.45 : 2,131.32 = 640.02 : x
  2. Step 2: Convert to fraction form
    1,420.45/2,131.32 = 640.02/x
  3. Step 3: Cross multiply
    1,420.45x = 2,131.32 × 640.02
  4. Step 4: Simplify right side
    1,420.45x = 1,364,087.43
  5. Step 5: Solve for x
    x = 1,364,087.43/1,420.45
  6. Step 6: Final answer
    x = 960.32

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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.