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Finding the Fourth Proportional to 857.19, 1,286 and 240.90

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Solution

The fourth proportional to 857.19, 1,286 and 240.90 is: 361.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    857.19 : 1,286 = 240.90 : x
  2. Step 2: Convert to fraction form
    857.19/1,286 = 240.90/x
  3. Step 3: Cross multiply
    857.19x = 1,286 × 240.90
  4. Step 4: Simplify right side
    857.19x = 309,797.40
  5. Step 5: Solve for x
    x = 309,797.40/857.19
  6. Step 6: Final answer
    x = 361.41

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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.