Home / 1,421.35-2,131.87-381.45

Finding the Fourth Proportional to 1,421.35, 2,131.87 and 381.45

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Solution

The fourth proportional to 1,421.35, 2,131.87 and 381.45 is: 572.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,421.35 : 2,131.87 = 381.45 : x
  2. Step 2: Convert to fraction form
    1,421.35/2,131.87 = 381.45/x
  3. Step 3: Cross multiply
    1,421.35x = 2,131.87 × 381.45
  4. Step 4: Simplify right side
    1,421.35x = 813,201.81
  5. Step 5: Solve for x
    x = 813,201.81/1,421.35
  6. Step 6: Final answer
    x = 572.13

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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.