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Finding the Fourth Proportional to 304.21, 419.86 and 221.21

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Solution

The fourth proportional to 304.21, 419.86 and 221.21 is: 305.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    304.21 : 419.86 = 221.21 : x
  2. Step 2: Convert to fraction form
    304.21/419.86 = 221.21/x
  3. Step 3: Cross multiply
    304.21x = 419.86 × 221.21
  4. Step 4: Simplify right side
    304.21x = 92,875.18
  5. Step 5: Solve for x
    x = 92,875.18/304.21
  6. Step 6: Final answer
    x = 305.30

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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.