Home / 1,418.41-2,128.26-638.61

Finding the Fourth Proportional to 1,418.41, 2,128.26 and 638.61

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Solution

The fourth proportional to 1,418.41, 2,128.26 and 638.61 is: 958.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,418.41 : 2,128.26 = 638.61 : x
  2. Step 2: Convert to fraction form
    1,418.41/2,128.26 = 638.61/x
  3. Step 3: Cross multiply
    1,418.41x = 2,128.26 × 638.61
  4. Step 4: Simplify right side
    1,418.41x = 1,359,128.12
  5. Step 5: Solve for x
    x = 1,359,128.12/1,418.41
  6. Step 6: Final answer
    x = 958.21

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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.