Home / 841.21-1,261.15-321.11

Finding the Fourth Proportional to 841.21, 1,261.15 and 321.11

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Solution

The fourth proportional to 841.21, 1,261.15 and 321.11 is: 481.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    841.21 : 1,261.15 = 321.11 : x
  2. Step 2: Convert to fraction form
    841.21/1,261.15 = 321.11/x
  3. Step 3: Cross multiply
    841.21x = 1,261.15 × 321.11
  4. Step 4: Simplify right side
    841.21x = 404,967.88
  5. Step 5: Solve for x
    x = 404,967.88/841.21
  6. Step 6: Final answer
    x = 481.41

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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.