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Finding the Fourth Proportional to 211, 315.78 and 203.80

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Solution

The fourth proportional to 211, 315.78 and 203.80 is: 305.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    211 : 315.78 = 203.80 : x
  2. Step 2: Convert to fraction form
    211/315.78 = 203.80/x
  3. Step 3: Cross multiply
    211x = 315.78 × 203.80
  4. Step 4: Simplify right side
    211x = 64,355.96
  5. Step 5: Solve for x
    x = 64,355.96/211
  6. Step 6: Final answer
    x = 305.00

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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.