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Finding the Fourth Proportional to 299.40, 412.90 and 216.20

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Solution

The fourth proportional to 299.40, 412.90 and 216.20 is: 298.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    299.40 : 412.90 = 216.20 : x
  2. Step 2: Convert to fraction form
    299.40/412.90 = 216.20/x
  3. Step 3: Cross multiply
    299.40x = 412.90 × 216.20
  4. Step 4: Simplify right side
    299.40x = 89,268.98
  5. Step 5: Solve for x
    x = 89,268.98/299.40
  6. Step 6: Final answer
    x = 298.16

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.