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Finding the Fourth Proportional to 686.21, 1,028.30 and 361.13

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Solution

The fourth proportional to 686.21, 1,028.30 and 361.13 is: 541.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.21 : 1,028.30 = 361.13 : x
  2. Step 2: Convert to fraction form
    686.21/1,028.30 = 361.13/x
  3. Step 3: Cross multiply
    686.21x = 1,028.30 × 361.13
  4. Step 4: Simplify right side
    686.21x = 371,343.03
  5. Step 5: Solve for x
    x = 371,343.03/686.21
  6. Step 6: Final answer
    x = 541.15

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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.